Mars |
The Mars Apparition of 2024-2025
by Martin J. Powell
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The path of Mars against the background stars from August 2024 to July 2025, shown at 10-day intervals (click on the thumbnail for the full-size image). During this apparition Mars describes a Northward-facing loop against the stars, in contrast to the hybrid formation that it described during the planet's previous apparition in 2021-23. The path of Jupiter over the same period is also shown, marked on the first day of selected months (see the Jupiter page for more details). A planetary conjunction between Mars and Jupiter takes place on August 14th 2024 (marked on the chart by the symbol ). For more details on this and seven other planetary conjunctions involving Mars, see below.
The star map applies to observers in the Northern hemisphere (i.e. North is up); for the Southern hemisphere view, click here. The faintest stars shown on the map have an apparent magnitude of about +4.8 (a few fainter stars are also plotted, which are referred to in the main text below). Printer-friendly versions of this chart are available for Northern and Southern hemisphere views. Astronomical co-ordinates of Right Ascension (longitude, measured Eastwards in hrs:mins from the First Point of Aries) and Declination (latitude, measured in degrees North or South of the celestial equator) are marked around the border of the chart. Click here to see the same star map without planet paths; observers may wish to use the 'clean' star map as an aid to plotting the planet's position on a specific night - in which case, a printable version can be found here. Photographs of this region of the night sky can be seen below.
The five star names shown in yellow-green were formally adopted by the International Astronomical Union (IAU) in 2017 and 2018.
At superior conjunction on November 18th 2023 (when it passes directly behind the Sun in the constellation of Libra, the Balance), Mars is positioned 2.5264 Astronomical Units (AU) from Earth (377.9 million kms or 234.8 million miles). Were it to be visible from Earth at this time, its apparent magnitude would be +1.4 and its apparent size only 3".7 (i.e. 3.7 arcseconds, where 1" = 1/60th of an arcminute or 1/3600 of a degree). Mars enters the constellation of Scorpius, the Scorpion, on November 25th, then Ophiuchus, the Serpent-Bearer, on December 5th and Sagittarius, the Archer, on December 31st.
Mars becomes visible in the dawn twilight from around the second week of January 2024 (Equatorial and Tropical latitudes), from mid-January (low and mid-Southern latitudes) and late January (low Northern latitudes). Mid and higher Northern latitudes begin to see Mars from around mid-March (at 40° North) and mid-May (50° North). Observers at higher Northern latitudes are the last to see the Red Planet come into view; from here it does not appear until early July. The delay in seeing the planet at Northern latitudes is due to a combination of lengthening twilight and the shallow angle of the ecliptic (the path along which the Sun, the Moon and planets follow closely) to the local Eastern horizon during this time.
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Mars reaches a solar elongation (angular distance from the Sun) of 15° West on January 9th 2024, at which time it is positioned in Eastern Sagittarius, at the far South of the zodiac. By this time it has become observable from Equatorial and Tropical latitudes. In mid-January Mars becomes visible from the Southern hemisphere and as far North as low-Northern latitudes, rising over the ESE horizon. As it enters the morning sky Mars, a first magnitude object at +1.3, is accompanied in the morning sky to its West by the inferior planets Mercury (magnitude -0.2) and Venus (mag. -3.9). Mercury, having passed its greatest Western elongation from the Sun on January 12th, is nearing the end of its first morning apparition of 2024. Venus is more than half-way through its 2023-24 morning apparition which began in the previous August. Mercury and Mars are in Western Sagittarius whilst Venus is in Southern Ophiuchus.
Mars at its Closest Approach to Earth in December 2022, imaged by Efrain Morales Rivera (Aguadilla, Puerto Rico) using a 305 mm (12-inch) Ritchey-Chrétien telescope fitted with a CMOS camera (click on the thumbnail for a larger version). Syrtis Major dominates the centre of the disk, whilst clouds hang over the planet's Northern polar region (Image: Jaicoa Observatory / ALPO-Japan)
Venus enters Sagittarius at 13 hours UT on January 20th, at which time it is 15°.6 to the West of Mars and 11°.2 to the West of Mercury. At midnight UT on January 27th Mercury is located only 0°.5 to the WNW of Mars whilst brilliant white Venus is 12°.5 to its West. At 1606 UT on the same day Mercury passes just 14'.5 (0°.24) to the North of Mars in the first of eight planetary conjunctions which take place during the Red Planet's 2024-25 apparition. A planetary conjunction occurs whenever any two planets attain the same celestial longitude, such that they appear close together in the night sky. This particular conjunction is only observable from latitudes South of about 37° North (for further details, refer to the Planetary Conjunctions section below). Over the next 6½ months Mars will pass all five of the other Solar System planets in the course of its circuit through the zodiac.
Mars' 2024-25 apparition truly gets underway as it reaches a solar elongation of 20° West on January 28th. At midnight UT on this date Mercury is positioned 19' (0°.31) to the North-east of Mars and is heading Eastwards towards the Sun at a rate of about 0°.5 per day. The Red Planet, on the other hand, is slowly pulling away from the Sun at a rate of just 0°.25 per day at this time. In late January Mars is rising in the ESE between 1 hour (30° North) and 1¾ hours (45° South) before the Sun.
Mercury continues to pull away from Mars over the coming week, brightening slightly from magnitude -0.2 to -0.3 over the period. At midnight UT, Mercury is 55' (0°.91) East of the Red Planet on January 29th, 2°.3 to the East of it on the 31st, 3°.7 to the East on February 2nd and 5°.2 to the East on February 4th. Over the same period Venus closes in on Mars. At midnight UT, Venus is positioned 11°.5 to the West of Mars on January 29th, 10°.6 to the West of it on the 31st, 9°.6 to the West of it on February 2nd and 8°.7 to the West of it on February 4th. Mercury enters Capricornus, the Sea-Goat, on February 5th and remains visible for a few more days until it disappears into the bright dawn twilight.
At this early stage in the apparition, Mars appears as a pale-orange 'star', shining about the same brightness as the star Antares ( Sco or Alpha Scorpii, mag. +1.3) in Scorpius, located some 40° to the WSW of the planet (this star has a distinct orange-red hue, rivalling the colour of the Red Planet). Mars barely gains any significant altitude before disappearing into the brightening dawn twilight. Telescopically, although the illuminated proportion of Mars' disk (phase) is over 98% (phase = 0.98), Mars is a disappointing sight, its tiny apparent size of around 4" frustrating most attempts to obtain a clear view of its surface.
Between early and mid-February Venus continues to narrow the gap with Mars, moving towards it at a daily rate of about 0°.5. Taken at midnight UT, Venus is positioned 8°.2 to the West of Mars on February 5th, 7°.3 to the West of it on the 7th, 6°.4 to the West of it on the 9th and 5°.4 to the West of it on the 11th. The waning crescent Moon passes by the pair on February 7th and 8th.
Mars enters Capricornus on February 12th; at this time of year only the Western part of the constellation is observable for a brief period of time, rising at dawn between low-Northern and low-Southern hemisphere latitudes. On February 16th the planet passes 8º.1 South of the star Algedi (2 Cap or Alpha-2 Capricorni), an apparent naked-eye double star with Prima Giedi (1 Cap or Alpha-1 Capricorni, mag. +4.2). Mars passes 5º.6 South of another double star, Dabih (1 Cap or Beta-1 Capricorni, mag. +3.1), on February 17th, with Venus 2º.5 to its West, having just entered the Sea-Goat.
At 1534 UT on February 22nd Venus finally catches up with Mars, passing to the North of the Red Planet in the second planetary conjunction of its 2024-25 apparition. It is well-placed for Southern hemisphere observers but poorly placed for those in the Northern hemisphere. At magnitude -3.8 gibbous Venus currently shines over 100 times brighter than Mars (mag. +1.3) and, through telescopes, appears over 2½ times larger than the Red Planet. For an assessment of the observability of this conjunction, see the Planetary Conjunctions section below.
Following conjunction, Venus speeds on towards the ENE through central Capricornus, pulling away from Mars as it heads in the direction of the Sun. At midnight UT, it is positioned 57' (0°.95) to the North-east of Mars on February 24th, 1°.8 to the ENE of it on the 26th, 2°.6 to the ENE of it on the 28th and 3°.6 to the ENE of it on March 1st.
Table showing the position and apparent magnitude of Mars for the early part of the 2024-25 apparition (click on the thumbnail for the full-size table). The magnitudes, diameters and solar elongations listed here refer to the middle of the period in question. In this and the tables which follow, the rising and setting directions of the constellations listed can be found by referring to the zodiacal constellation rise-set direction table.
At 10 hours UT on March 2nd Mars passes 30' (0º.5) South of Cap (Theta Capricorni, mag. +4.0), which is positioned at the centre of the Sea-Goat. At 1630 UT on March 7th the planet passes 16' (0°.26) North of the star Cap (Iota Capricorni, mag. +4.2), which is positioned at the 'rump' of the Sea-Goat figure. Venus enters Aquarius, the Water-Carrier, at 20 hours UT on March 9th, positioned 7°.7 to the ENE of Mars.
The Western half of Aquarius is located several degrees to the North of Mars at this time. Its brightest star is Sadalsuud ( Aqr or Beta Aquarii, mag. +2.9), a name which is Arabic for 'the lucky one of the lucky', its meaning having astrological origins. Mars passes 10º.2 South of Sadalsuud on March 10th; it is currently only observable from latitudes South of about 35º North. From North of the Equator, the star rises shortly before the Red Planet; from South of the Equator it rises shortly after it.
Mars passes 1°.5 North of Nashira ( Cap or Gamma Capricorni, mag. +3.7) on March 13th and 1°.4 North of Deneb Algedi ( Cap or Delta Capricorni, mag. +2.9), the brightest star in the constellation, on the 15th. Both stars are currently only observable at dawn from South of about 25° North. Deneb Algedi is Arabic for 'tail of the goat' and it was also known as Deneb Algiedi or Scheddi before IAU standardisation in 2017.
From around the middle of March, the planet Saturn (mag. +0.8) begins to emerge into the dawn sky, positioned in central Aquarius some 17° to the ENE of Mars and 6° to the ENE of Venus. The ringed planet is at the start of its 2024-25 apparition, which will see it reach its peak brightness (+0.3) at opposition in September. In mid-March Mars approaches Saturn at a rate of about 0°.7 per day. Taken at midnight UT, Saturn is 16°.5 to the ENE of the Red Planet on March 17th, 15°.2 to the ENE of it on the 19th and 13°.9 to the ENE of it on the 21st. Venus and Saturn are themselves in conjunction on the 22nd, Venus passing 20' (0°.33) to the North of the ringed planet at 02 hours UT, with Mars positioned 13°.2 away to their WSW.
Mars enters Aquarius at around 16 hours UT on March 19th, a constellation which, at the present time, can only be fully observed from latitudes South of the low-Northern hemisphere. The planet passes 12º.6 South of the constellation's second-brightest star Sadalmelik ( Aqr or Alpha Aquarii, mag. +2.9) on March 21st, then 1°.0 North of the star Aqr (Iota Aquarii, mag. +4.2), at the 'knee-joint' or 'hip' of the Water Carrier (depending upon the star map depiction) at 05 hours UT on March 22nd. Mars passes 4º.1 South of the star Ancha ( Aqr or Theta Aquarii, mag. +4.1), in central Aquarius, on March 25th.
From around the third week of March, observers at latitudes in the vicinity of 40º North begin to see Mars emerge into the dawn sky, rising in the ENE about 1¼ hours before sunrise. Further to the South the planet is also rising in the ESE, at around 2 hours (Equator), 2½ hours (25° South) and 3 hours (45° South) ahead of sunrise.
Saturn is located 12°.5 to the ENE of Mars on the 23rd and 11°.2 to the ENE of it on the 25th. Venus, Saturn and Mars are equi-distant at around 09 hours UT on March 29th, spread from central to North-eastern Aquarius, there being 18°.3 angular distance between both Venus and Saturn and Saturn and Mars.
A Distant Mars in January 2022, imaged by Eric Sussenbach (Willemstad, Curaçao) in the early (morning) stage of the planet's 2021-23 apparition. Sussenbach used a 279 mm (11-inch) aplanatic Schmidt reflector telescope fitted with a planetary camera. Mars was 36° West of the Sun and only 4".3 in apparent diameter (Image: Eric Sussenbach / ALPO-Japan)
From March 27th to 31st Mars is positioned about 11º South of Aquarius' best-known naked-eye feature, an asterism (star pattern) informally known as the 'Steering Wheel'. On older star maps it marked the amphora from which the Water-Carrier poured his water, though on more recent star maps it sometimes appears as the Water-Carrier's head. At the centre of the 'wheel' is the star Aqr (Zeta Aquarii, mag. +3.7) with the stars Sadachbia ( Aqr or Gamma Aquarii, mag. +3.9), Aqr (Eta Aquarii, mag. +4.0) and Aqr (Pi Aquarii, mag. +4.8) encircling it. It is one of several asterisms in the zodiac with which beginner astronomers should become familiar. Mars passes 10º.0 South of Sadachbia on March 27th and 10º.7 South of Aqr on the 29th. At 0821 UT on March 30th Mars passes just 43" (0'.71 or 0º.012) North of Aqr (Sigma Aquarii, mag. +4.8), an apparent distance which at the current time is equivalent to just under ten apparent Mars diameters. Sigma Aquarii is a double star located at the approximate centre of Aquarius. The planet passes 10º.0 South of Aqr - at the Eastern edge of the 'wheel' - on March 31st.
Mars passes 4º.8 North of the star 2 Aqr (Tau-2 Aquarii, mag. +4.0) on April 5th and 0º.9 South of the star Aqr (Lambda Aquarii, mag. +5.8) at 20 hours UT on April 6th. The waning crescent Moon passes by Mars, Saturn and Venus between April 6th and 7th. Also on April 7th, Mars passes 7º.6 North of the star Skat ( Aqr or Delta Aquarii, mag. +3.2) which on old star maps marked the Water-Carrier's lower right leg.
Far to the South of Mars in April is the constellation of Piscis Austrinus, the Southern Fish. Ancient Greek and Babylonian mythology describes it as being the parent of the much more famous zodiacal Pisces and it was envisaged as drinking the water poured from the Waterman's amphora. The constellation's brightest star is Fomalhaut ( PsA or Alpha Piscis Austrini, mag. +1.2), a blue-white star whose Arabic name translates as the 'fish's mouth'. With a declination () of -29º.6 it cannot be seen North of latitude 60º.4 North. Even at mid-Northern latitudes the star's altitude at meridian transit is low, reaching just 10º above the Southern horizon at 50º North and 20º above the horizon at 40º North. From the Northern hemisphere the star shines in splendid isolation, being the brightest star for some distance around it. Mars passes 21º.9 North of Fomalhaut on April 8th but the star is a prominent object to the South of the Red Planet throughout its passage of Aquarius.
Mars catches up with Saturn at 0312 UT on April 11th, passing just 28' (0º.46) to the North of it in the third planetary conjunction of the apparition. It is one of only fifteen occasions during this century when the two planets come to within 1° of each other. This close conjunction is well-placed for Southern hemisphere observers. Through a telescope, Saturn's rings present a shallow angle to the Earth since they are now closing; they are only one year away from being seen edge-on to us. Saturn's globe - whose North pole is tilted slightly in our direction - appears about 16" across whilst the rings are about 36" across. By comparison, the Martian disk appears just 4".6 across, 3½ times smaller than Saturn's globe. Mars appears gibbous (phase = 0.95) whilst Saturn appears more-or-less fully illuminated - a consequence of Solar System geometry and the two planets' greatly differing distances from Earth (Saturn being five times further away than Mars). For more details on the observability of the conjunction by latitude, see below.
The conjunction having passed, Mars leaves Saturn behind it, the Red Planet being 57' (0°.95) to the North-east of the ringed planet at midnight UT on April 12th, 1°.6 to the North-east of it on the 13th and 2°.2 North-east of it on the 14th.
At 08 hours UT on April 14th Mars passes 13' (0°.21) South of the star Aqr (Phi Aquarii, mag. +4.2), which on older star maps is one of several stars which marked the stream of water which flowed from the Water-Carrier's amphora; more recent maps have shown it marking the top of his amphora. At 21 hours UT on the same day the planet passes 3°.0 North of the star 1 Aqr (Psi-1 Aquarii or 91 Aquarii), also magnitude +4.2, another star in the water stream. In 2013 the star, which is 144 light years distant (where 1 light year = 63,241 AU), was found to have an extra-solar planet or exoplanet (a planet outside our own Solar System) orbiting around it. Designated 91 Aquarii b, it is a gas giant of around 3.2 Jupiter masses which orbits the star in a period of 181 days at a local distance of 0.7 AU (about the same distance from the Sun as Venus in our own Solar System). Psi-1 Aquarii is one of around 170 naked-eye stars in the night sky which are known to host exoplanets; several others will be described below, as Mars passes each in turn.
Between April 15th and 25th, Mars is positioned several degrees South of the Circlet of Pisces, which is located at the Western end of Pisces, the Fishes. The Circlet comprises six stars of fourth and fifth magnitude, although under suburban skies it is likely that some or all of them will not be seen with the naked-eye. The passage begins at 09 hours UT on April 15th when the planet passes 9°.1 South of Aqr (Gamma Piscium, mag. +3.7), the Westernmost star of the Circlet. It is another star which, in 2021, was found to host an exoplanet, designated Gamma Piscium b. Some 135 light years distant, it has a mass equivalent to 1.3 Jupiters and takes 1½ years to complete an orbit of its star at a local distance of 1.3 AU.
Also on April 15th, Mars passes two more stars in the water stream: 3°.3 North of 2 Aqr (Psi-2 Aquarii, mag. +4.2) at 15 hours UT and 3°.8 North of 3 Aqr (Psi-3 Aquarii, mag. +5.0) at 23 hours UT. At 0240 UT on April 16th the planet passes 36' (0°.6) South of the star 96 Aqr (96 Aquarii, mag. +5.7), a double star with a magnitude +10.4 companion located 10" distant. Mars will occult (pass in front of) this star in the evening sky in January 2032.
On April 21st Mars presents its maximum Southerly aspect for this apparition, when its Southern Pole is tilted towards the Earth at 25°.7. The angle is sometimes listed in astronomical tables as DE, i.e. the declination of the Earth as measured from the centre of Mars (the values of DE for the period covered by the star chart are listed under 'Tilt' in the data table below). Given that the axial inclination of Mars to the plane of its orbit is 25°.2, this is about as high an inclination that the Red Planet can present to the Earth.
From the third week of April, Mercury (mag. +3.2) returns to the morning sky at the start of its second morning apparition of 2024. This particular apparition favours Southern hemisphere observers, from where the ecliptic is inclined at a steep angle to the Eastern horizon at dawn at this time of year. As it returns Mercury is retrograding in central Southern Pisces, located about 24° to the ENE of Mars. Over the coming days the two planets quickly narrow the gap between them, closing in on each other at a rate of about 1° per day. At midnight UT, Mercury is positioned 23°.1 to the ENE of Mars on April 22nd, 22°.2 to the ENE of it on the 23rd and 21°.2 to the ENE of it on the 24th. Also on the 24th, Mars enters Pisces through its South-western border at around 02 hours UT.
Mars completes its passage of the Circlet at 15 hours UT on April 25th when it passes 6°.2 South of the star TX Psc or 19 Psc (19 Piscium, mag. +5.1v), positioned at the Eastern end of the asterism. It is a red giant variable star with a small irregular brightness variation of between magnitudes +4.8 and +5.2.
Mercury reaches its Western stationary point on April 24th and over the next few days its motion turns direct (or prograde); during this time Mars closes the gap with Mercury at a rate of 0°.8 per day. Taken at midnight UT, Mercury is positioned 20°.3 to the ENE of Mars on the 25th, 19°.5 to the ENE of the Red Planet on the 26th, 18°.8 to the ENE of it on the 27th and 18°.2 to the ENE of it on the 28th. Mars reaches a solar elongation of 40° West on April 27th.
At 0402 UT on April 29th Mars (mag. +1.1) passes just 2'.3 (0°.04) to the South of the planet Neptune (+7.9) in another planetary conjunction which is ideally placed for Southern hemisphere observers. The blue ice giant first entered Pisces in May of 2022 then, having retrograded back into Aquarius twice since August of that year, re-entered Pisces in March of 2023. In April 2024 Neptune is five months away from opposition and is only 0.1 magnitude below its peak brightness for the year. As Mars passes the Solar System's most distant 'true' planet its rate of motion is some 25 times faster. This an ideal opportunity for those who have never seen our most distant Solar System planet to locate it with relative ease, using Mars as a bright locator-beacon. Refer to the section below for more details on the observability of the conjunction.
Having now passed the Circlet, Mars passes 8º.2 South of the star Psc (Omega Piscium, mag. +4.2), located at the Southern fish's tail, on April 30th. Mercury, having brightened to magnitude +1.3, is currently positioned 17°.2 to the ENE of Mars. Meanwhile Venus, now just entering Aries, the Ram, heads out of naked-eye view in the dawn twilight, bringing its 2023-24 morning apparition to a close.
Mars crosses to the North of the celestial equator on May 4th, the planet rising due East across the inhabited world at this time. At around 22 hours on the same day Mercury (mag. +0.9), Mars and Saturn are equi-distant, the angular distance between Mercury-Mars and Mars-Saturn being 16º.2. The waning crescent Moon passes by the trio between May 3rd and 6th.
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Mars reaches perihelion (its closest orbital position to the Sun) on May 8th, positioned at a distance of 1.3815 AU (206.6 million kms or 128.4 million miles) from the Sun. Its most distant position from the Sun, known as the aphelion, will be reached one-half of a Martian orbit later, in April 2025.
From around midnight UT on May 5th Mars is involved in a lunar occultation, one of several such events which take place during the planet's 2024-25 apparition. A lunar occultation occurs when the Moon passes in front of a planet, blocking it from view for a short period of time. Because of the rotating Earth, the relative closeness of the Moon to the Earth and the consequent effect of parallax, any given lunar occultation can only be observed from a particular region of the world. The May 5th occultation takes place when the Moon is a 26-day-old waning crescent, the planet disappearing behind the Moon's bright Eastern limb and re-appearing from behind its dark (shadowed) Western limb. The event is visible in twilight/darkness (depending upon the precise observing location) from the South-western Indian Ocean. For a map and timings of this event, follow the link provided in the Moon near Mars section below.
Mercury, now magnitude +0.8, comes to within 16°.1 of Mars on May 6th; they will not reach conjunction on this occasion since Mars is too far away from the Sun. On May 7th Mars passes 9°.6 North of Cet (Iota Ceti, mag. +3.5), located at the tail-end of Cetus, the Whale. It has been known by the name Deneb Kaitos Shemali but this is mostly not used now because of confusion with the nearby star Diphda ( Cet), the brightest star in the constellation, which was formerly known as Deneb Kaitos. The original Arabic names of these stars translated as 'tail of the whale' to the North ( Cet) and South ( Cet).
Mercury (mag. +0.6) reaches its greatest elongation (26°.4 West of the Sun) on May 9th, positioned 16º.3 to the ENE of Mars. At 17 hours UT on the same day Mars leaves the zodiac for a little under four days as it cuts across the North-western corner of Cetus.
Now speeding towards the ENE through the tail of the Fishes, Mercury pulls away from Mars over the coming days. At midnight UT, Mercury is positioned 16°.5 to the ENE of Mars on May 10th, 16°.8 to the ENE of the Red Planet on the 11th, 17°.1 to the ENE of it on the 12th and 17°.4 to the ENE of it on the 13th. During this period Mercury brightens slightly from magnitude +0.6 to +0.4.
Mars re-enters Pisces through its Southern border at 16 hours UT on May 13th, having traversed a 3º-wide section of the Whale over the course of about 95 hours; this equates to an average daily motion against the stars of 0º.76. On May 15th Mars passes 21º.4 North of the aforementioned star Diphda ( Cet or Beta Ceti, mag. +2.0), which is located at the South-western corner of Cetus.
By mid-May observers at mid-Northern latitudes begin to see Mars rising in twilight, positioned low over the Eastern horizon just before dawn. The planet is now rising at the following periods before sunrise: 1½ hours (50° North), 2 hours (30° North), 2¾ hours (Equator), 3 hours (15° South), 3¼ hours (25° South) and 4 hours (45° South).
Mars passes 3º.6 South of the star Psc (Delta Piscium, mag. +4.4), positioned about half-way along the Southern Fish of Pisces, on May 17th. The star is one of several which on old star maps mark the long and winding cord between the Northern and Southern Fishes.
Mercury (mag. +0.1) temporarily enters Cetus at 03 hours UT on May 18th, positioned 19º.8 to the ENE of Mars, then enters Aries at 22 hours UT on the 19th, 20º.9 away from Mars.
On May 22nd Mars passes 2º.5 South of the star Psc (Epsilon Piscium, mag. +4.2), another star in the meandering cord. Positioned 2°.7 to the East of Psc is the double star Revati ( Psc or Zeta Piscium, mag. +4.9), a Sanskrit name derived from an ancient Hindu lunar mansion.. The name was assigned to the star in 2017 by the Working Group on Star Names (WGSN), a newly-established division of the IAU which since 2016 has been cataloguing and standardizing the star names used by the international astronomical community. In order to accommodate a wider diversity of global culture, the WGSN has adopted some names from mythologies other than Arab, Greek and Roman, whose star names dominate the night sky. Mars passes 1°.0 South of Revati at 1830 UT on May 26th. The star comprises two components of magnitude +5.2 and +6.3, separated by a wide 23" (0'.4) and easily split in small telescopes. Mars passes several other 'newly-named' stars during its 2024-25 apparition, many of which will be mentioned below, along with a number of better-known star names (proper names) for which the IAU have now introduced standardized spellings.
Speeding Eastwards through Southern Aries, Mercury is located to the ENE of Mars through to the end of its apparition. Taken at midnight UT, its angular distance from the Red Planet is 23°.1 on May 23rd, 24°.7 on the 25th, 26°.5 on the 27th and 28°.5 on the 29th. The planet brightens rapidly during this period, from -0.1 (on the 23rd) to -0.5 (on the 29th). Mercury enters Taurus, the Bull, at 19 hours UT on May 30th and over the next few days becomes lost from view in the dawn twilight.
Mars passes 2º.0 North of Psc (Mu Piscium, mag.+4.8) at 11 hours UT on June 1st. At 23 hours UT on the same day Mars passes 7°.0 South of the star Alpherg ( Psc or Eta Piscium, mag. +3.8), the brightest star in Pisces, then 3°.8 North of Psc (Nu Piscium, mag.+4.4) on June 5th. All three of these stars are located along the cord.
Mars at 91% Phase in April 2022, imaged by Mark Lonsdale (Midgard Observatory, Canberra, Australia) using a 356 mm (14-inch) aplanatic Schmidt reflector telescope fitted with a CMOS camera (click on the thumbnail for a larger version). The planet measured 5".3 in apparent diameter (Image: Mark Lonsdale / ALPO-Japan)
At 2035 UT on June 6th Mars passes just 31' (0º.51) North of the star Torcular ( Psc or Omicron Piscium, mag. +4.2), which is positioned about one-third of the way along the Northerly section of the cord. The star's long-form name is Torcularis Septentrionalis which is a mis-translation of an original Greek word meaning 'flax', i.e. the aforementioned cord that tied the two fishes' tails together.
On June 9th Mars passes 8º.7 South of the double star Mesarthim ( Ari or Gamma Arietis, mag. +3.9), on the Western side of Aries. Easily resolved in small telescopes, it comprises two white stars of magnitudes +4.6 and +4.7, separated by 7".5. The name Mesarthim is Arabic in origin but its meaning is unclear, however it has been associated with the nearby star Sheratan ( Ari or Beta Arietis, mag. +2.6) since ancient times, when the stellar pair were considered to mark the New Year.
From around the second week of June the giant planet Jupiter emerges into the morning sky, at the start of its 2024-25 apparition. Positioned some 33º away to the ENE of Mars, Jupiter is in the far North of the zodiac in central Taurus and currently shines at magnitude -1.8. It will reach opposition, at magnitude -2.8, in December. The two planets will pass each other in mid-August.
Mars enters Aries at around 02 hours UT on June 10th, passing 10º.2 South of the aforementioned Sheratan (Arabic for 'the signs') at 05 hours UT on the same day.
Mars passes 8°.5 North of the double star Alrescha ( Psc or Alpha Piscium, mag. +3.8), in neighbouring Pisces, on June 12th. The name Alrescha was standardized by the IAU in 2016, the star having been previously known as Al Rischa, Alrisha or Al Rescha. It comprises two blue-white components of magnitudes +4.1 and +5.1, separated by an angular distance of 1".8 on a roughly East-West orientation. Telescopes of at least 75 mm (3 in) aperture are required to split the pair.
The Red Planet passes 11°.7 South of the Aries' brightest star Hamal ( Ari or Alpha Arietis, mag. +2.0) on June 14th. In 2010 the star was found to have an exoplanet, designated Alpha Arietis b. At 66 light years distant, its mass is equivalent to 1.8 Jupiters and it orbits the star in 381 days at a local distance of 1.2 AU. Mars passes between Alrescha and Hamal on June 13th.
By June 24th Mars has brightened to magnitude +1.0, thus continuing to be a first-magnitude object (a first-magnitude object being classed as lying between magnitudes +0.51 and +1.50). The planet will continue to be first-magnitude through to the end of September.
On June 27th Mars passes 11°.6 North of Kaffaljidhma ( Cet or Gamma Ceti, mag. +3.6) in Cetus, a double star comprising yellow and blue components of magnitude +3.5 and +7.0 separated by just 2".7. A telescope with an aperture of at least 60 mm (2½ inches) and high magnification is required to split them. The name is Arabic for 'the palm of the hand'.
In the Northernmost realm of Aries is the star Lilii Borea (39 Ari or 39 Arietis, mag. +4.5), a Latin name meaning 'Northern Lily'. The name was formally recognised by the IAU in 2017 and it first appeared in a 1757 star catalogue compiled by the French astronomer Nicolas-Louis de Lacaille (1713-1762). The lily to which he referred was the short-lived constellation Lilium, the Lily, a fleur-de-lis placed in this part of the sky by another Frenchman, Ignace-Gaston Pardies (1636–1673), in honour of King Louis XIV. Mars passes 13º.9 South of Lilii Borea at 0330 UT on June 29th. Two degrees to the SSE of Lilii Borea is the variable and double star Bharani (41 Ari or 41 Arietis, mag. +3.6), named after the second lunar mansion in Hindu astrology. It is another name which was adopted by the IAU in 2017. Mars passes 11º.8 South of the star at 2130 UT, also on the 29th.
On July 2nd the planet passes 5º.2 South of Ari (Epsilon Arietis, mag. +4.6), which is also both a double star and a variable star. Its two white components are magnitudes +5.2 and +5.5 and are separated by just 1".5, requiring telescopes of at least 100 mm (4 in) and high magnification in order to split them.
Mars passes 12°.2 North of the red giant star Menkar ( Cet or Alpha Ceti, mag. +2.5) on July 4th. Binoculars show an apparent blue companion star of magnitude +5.6 close by, but this is only a line-of-sight effect; the star is actually over six times more distant than Menkar. The name is Arabic for 'the nose', i.e. the nose of the Whale, and it should not be confused with Minkar ('the beak'), a star on the opposite side of the celestial sphere in the constellation of Corvus, the Crow.
Almost six months after the start of the apparition, in early July, observers at high-Northern latitudes finally see Mars emerge into the ENE sky at dawn, although it is seen in continuous twilight. With the planet's elongation now around 55° West of the Sun, Mars gains sufficient altitude above the horizon to be observed briefly before the twilight overwhelms it. Elsewhere the planet is rising in the ENE some 3¼ hours (50° North), 3½ hours (30° North), 4 hours (15° South) and 4¼ hours (45° South) before sunrise.
On July 7th Mars passes 2º.8 South of the star Botein ( Ari or Delta Arietis, mag. +4.3) which on older star maps marked the hind leg of the Ram.
Mars enters Taurus at 15 hours UT on July 11th, passing 8º.8 North of the star Tau (Omicron Tauri, mag. +3.6), the Westernmost bright star of the constellation, six hours later.
At 0923 UT on July 15th Mars passes 0º.5 to the South of Uranus in the fifth observable planetary conjunction of the 2024-25 apparition. As Mars passes the ice giant its daily apparent rate of motion is seventeen times faster. Uranus will reach opposition in November, when it will shine 0.2 magnitudes brighter. For details on the observability of this conjunction, which favours the Southern hemisphere, see below.
Having passed Uranus, Mars sets its sights on Jupiter, now only 12° away to its East. In mid-July Mars is closing in on Jupiter at a daily rate of about 0º.5.
Between July 18th and 20th Mars passes several degrees South of the Bull's most famous asterism known as the Pleiades or Seven Sisters (Messier 45 or M45). It passes 5º.0 South of the cluster's brightest Western star (Electra, mag. +3.7) at around 22 hours UT on the 17th, completing its passage at around 10 hours UT on the 20th, when it passes 4º.7 South of the cluster's brightest Eastern star (Atlas, mag. +3.6).
At 11 hours UT on July 24th Mars passes 7°.4 North of the eclipsing binary star Tau (Lambda Tauri), positioned at the upper 'chest' of the Bull figure, whose magnitude varies from ca. +3.5 to +4.0 over a period of four days.
By the final week of July Mars is rising in darkness across the inhabited world. Before disappearing from view in the twilight the planet reaches 24° in altitude in the East at 60° North, 43° high in the East at 40° North, 54° high in the East at the Northern Tropics and 54° high in the North-east at the Equator. For the Southern hemisphere the altitudes and directions are as follows: 46° high in the North-east at 15° South, 40° high in the NNE at the Southern Tropics, 33° high in the NNE at 35° South and 24° high in the NNE at 45° South.
Mars enters the star chart coverage (above) on July 25th, positioned about 5°.5 South-east of the Pleiades.
Table of selected data relating to the brighter part of the Mars apparition of 2024-25, for 0 hrs UT on the dates shown (click on the thumbnail for the full-size table). The data is listed at 10-day intervals, corresponding with the dates on the star map.
The Central Meridian Longitude (provided for telescopic observers) is the Martian longitude which appears at the centre of the disk when seen from the Earth. A Martian longitude map by Damian Peach showing the surface features can be seen at the ALPO-Japan website (note that the map is shown with South up, matching the inverted view seen through astronomical telescopes). For example, when CM = 290°, Syrtis Major appears at the centre of the disk. The Central Meridian Longitude increases by 14°.6 every hour, so this allowance should be applied for observations at other times (if the result is greater than 360°, subtract 360° to obtain the correct longitude). The Tilt is the angle at which Mars' North pole is tilted towards (+) or away from (-) the Earth; it is the declination of Earth as seen from Mars.
Those wishing to observe Mars telescopically should consider downloading the free 'Mars Previewer II ' software by Leandro Rios, available as a ZIP file at Sky & Telescope.
The data for the table was obtained from 'RedShift 5', ''SkyGazer Ephemeris' and 'Mars Previewer II' software. The Martian disk images were derived from NASA's Solar System Simulator; they appear at the same scale as those in the Mars Opposition data table here.
At around 0019 UT on July 26th Mars encounters the first of seven occultations of stars between 8th and 10th magnitude that the planet will experience during 2024. Like lunar occultations, such events can only be seen from very specific regions of the world when under ideal sky conditions. However, since the stars involved are well below naked-eye magnitude they require binoculars or telescopes to observe. On this occasion the star occulted is designated TYC 1258−00868−1 (after the Tycho-2 catalogue of 2.5 million Milky Way stars, published in 2000) and is of magnitude +8.4. The star disappears behind Mars' bright Eastern limb and, up to 201 seconds later, re-appears from behind its dark Western limb. The event is observable in twilight/darkness from Western Asia, the Middle East, North-eastern Africa and Eastern Europe. For a detailed finder chart and a visibility map visit the Belgian VVS website.
At 0920 UT on July 27th Mars passes 43' (0°.71) North of the star 1 Tau (Omega-1 Tauri, mag. +5.5), positioned in central Taurus some 6°.9 to the South-east of the Pleiades and 1°.3 South of the ecliptic. At 0525 UT on July 30th the planet passes just 8' (0°.13) North of 2 Tau (Omega-2 Tauri, mag. +4.9), positioned 2°.1 to the ENE of its fainter namesake.
During the final week of July Jupiter is positioned less than 10º to the East of Mars; as the waning crescent Moon passes by the pair in the final couple of days, Jupiter is 7º.7 from the Red Planet at midnight UT on July 30th and 7º.2 from it at midnight UT on the 31st.
Between July 31st and August 5th Mars passes several degrees to the North of a large star cluster called the Hyades, a distinct 'V'-shaped grouping of stars which form the head of the Bull. The cluster comprises around 400 stars spread over an exceptionally large area of about 5° of the sky. On July 31st Mars passes 5°.2 North of the star Prima Hyadum ( Tau or Gamma Tauri, mag. +3.6), positioned at the apex of the 'V'. Before the name was standardized by the IAU in 2017, the star was known variously as Primus Hyadum or Hyadum I. On August 1st Mars passes 3°.4 North of Secunda Hyadum (1 Tau or Delta-1 Tauri, mag. +3.7), a triple star system positioned about half-way along the Northern arm of the cluster. Before IAU standardization the star was also known as Secundus Hyadum or Hyadum II.
Positioned a few degrees North of the Hyades is a grouping of stars of between 4th and 6th magnitude which straddle the ecliptic. At 02 hours UT on August 2nd Mars passes 1°.1 South of the stars 1 Tau (Kappa-1 Tauri, mag. +4.2) and 2 Tau (Kappa-2 Tauri, mag. +5.2). Eight hours later the planet passes 1°.7 South of Tau (Upsilon Tauri, mag. +4.3). At 18 hours UT on the same day it passes 1°.8 South of 72 Tauri (mag. +5.5). Mars will come to within 4" (0°.001) of this star in March 2036.
Alos positioned along the Northern arm of the Hyades is the star Ain ( Tau or Epsilon Tauri, mag. +3.5), which on older star maps marked one of the Bull's eyes. Mars passes 2°.0 North of the star at 05 hours UT on August 3rd. In 2006 the star was found to host an exoplanet, technically named Epsilon Tauri b but having a proper name of Amaterasu, after a Japanese sun goddess. Some 155 light years distant, it has a mass equivalent to 7.6 Jupiters and it orbits Ain in 1.6 years at a local distance of 1.8 AU. At the same moment as passing Ain, Mars passes 5°.4 North of Chamukuy (2 Tau or Theta-2 Tauri, mag. +3.7), positioned about half-way along the Southern arm of the cluster. The name is that of a small bird in Yucatec Mayan culture and it was adopted by the IAU in 2017. The star forms a naked-eye yellow-white double with 1 Tau (Theta-1 Tauri, mag. +3.8), positioned some 5'.6 (0°.09) to the North.
Prior to 2025, Mars last reached opposition between the horns of Taurus in early December 2022. This photograph, taken by the writer in late November 2022, shows the Red Planet two days before its closest approach to the Earth, when it shone at magnitude -1.8 (click on the thumbnail for the full-size photo). Click here to see an annotated version of the photograph.
On August 5th Mars passes 5°.0 North of Aldebaran ( Tauri, mag. +0.9), the brightest star in Taurus, positioned at the South-eastern corner of the 'V' and marking the other 'eye' of the Bull. Aldebaran appears orange-red to the naked-eye since it is a red giant star. It appears to be part of the cluster but in fact, it is not a physical member of the Hyades group; its appearance in the cluster is purely a line-of-sight effect. The Hyades lie at a distance of about 150 light years from Earth whereas Aldebaran is much closer, at 67 light years. Aldebaran has an exoplanet, designated Alpha Tauri b, with a mass equivalent to 6½ Jupiters. Discovered in 2015, it orbits Aldebaran in a period of 1.7 years at a local distance of 1.46 AU (roughly the same distance as Mars from the Sun in our own Solar System).
On August 8th Mars passes 1°.2 South of Tau (Tau Tauri, mag. +4.2), another star which, like Aldebaran, is not part of the Hyades group. Positioned at the base of the Bull's Northern horn, it is a multiple-star system and a member of an obscure open cluster known as Alessi 51.
From the second week of August, Mars passes to the North of Orion, the Hunter, perhaps the most recognisable constellation in the night sky. Orion emerged into the morning sky between late June and early August (depending upon the observer's latitude) and is now in the early stage of its seasonal appearance, rising due East at dawn. The Red Planet passes North of Orion's bow, comprising the stars Tabit (3 Ori, or Pi-3 Orionis, mag. +3.2) at the centre, 1 Ori (Pi-1 Orionis, mag. +4.6) at the top and 6 Ori (Pi-6 Orionis, mag. +4.5) at the base, between August 10th and 12th.
Mars and Jupiter are now within a few degrees of each other. At midnight UT, Jupiter is 2°.3 to the East of the Red Planet on August 10th, 1°.8 to the East of it on the 11th, 1°.3 to the East of it on the 12th and 51' (0°.85) to the ESE of it on the 13th.
Located to the North-east of Taurus is the six-sided figure comprising the stars of Auriga, the Charioteer. Mars passes 10°.8 South of Hassaleh ( Aur or Iota Aurigae, mag. +2.5), at the South-western corner of the constellation, on August 13th.
Mars and Jupiter meet in conjunction at 1649 UT on August 14th, positioned some 48' (0°.8) North-west of the star Tau (Iota Tauri, mag. +4.6) and 9°.5 to the ENE of the Hyades' centre. The pair are separated by an apparent distance of 18' (0°.3) and the solar elongation is a comfortable 65°. The two planets are easily contained within a wide-field telescope field of view, Mars having increased in apparent size to 6".1 and Jupiter, six times larger at 37".1 across, providing a contrasting visual treat. This is the only one of the eight Mars conjunctions in the 2024-25 period which is favourable for Northern hemisphere observers. For more details, refer to the Planetary Conjunctions section below.
Mars passes 1°.2 North of the aforementioned Tau (Iota Tauri, mag. +4.6), which is positioned in the central space between the Bull's horns, at 21 hours UT on August 15th, with Jupiter trailing 43' (0°.71) behind the planet to its WSW.
At around 1036 UT on August 19th Mars occults the magnitude +8.9 star TYC 1846−00598−1, an event which is visible in twilight/darkness from Southern Mexico, the South-western Caribbean, Western South America and the South-eastern Pacific Ocean. The star disappears behind the planet's bright Eastern limb and re-emerges from behind its dark Western limb up to 233 seconds later. For a detailed finder chart and a visibility map visit the Belgian VVS website.
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Mars passes 23°.0 South of Auriga's brightest star Capella ( Aur or Alpha Aurigae, mag. +0.1) on August 20th. Capella comprises two yellow stars orbiting each other; it is a spectroscopic binary, meaning that the secondary star is so close to its parent star that it can only be detected by observing Doppler shifts in its spectral lines. Capella is the third brightest star in the Northern celestial hemisphere and the sixth brightest star in the entire night sky. It often catches the eye of observers in mid-Northern latitudes during summer nights, when it is seen low over the Northern horizon. Capella is circumpolar from latitudes North of 44° North, meaning that from these latitudes it is always above the horizon.
Mars passes 44' (0°.73) North of 109 Tau (109 Tauri, mag. +4.9) at 0710 UT on August 21st, then 16°.8 North of Bellatrix ( Ori or Gamma Orionis, mag. +1.6), the North-western corner star of Orion's distinctive quadrilateral, on August 23rd. Later that same day the planet passes 5°.6 South of the star Elnath ( Tau or Beta Tauri, mag. +1.6), which is located at the tip of the Bull's Northern horn. The name was standardized by the IAU in 2016, previous versions of the name being spelled Al Nath, El Nath or simply Nath. Elnath also doubles-up as the Southernmost star of Auriga, located to the North-east of Taurus; in fact, historically it was known by the designation Aur (Gamma Aurigae).
On August 24th telescopic observers see Mars with an apparently straight equator, as the Earth passes from the South of the Red Planet's equatorial plane to the North of it. At this point the declination of Earth as seen from the centre of Mars (DE) is 0°.0, the planet's polar axis being tipped about 30° to the West of celestial North.
Following their conjunction in mid-August, the angular distance between Mars and Jupiter has increased significantly. By midnight UT on August 24th Mars is 4°.6 to the West of Jupiter and by month's end they will be 8°.2 apart.
At 2030 UT on August 26th Mars passes 1°.1 North of the Crab Nebula (M1 or NGC 1952), the gaseous remnant of a supernova which exploded in 1054 AD. It is a faint object, just visible in binoculars under dark skies and an elongated wisp when seen through telescopes. The nebula was first observed in 1731 by English physician and amateur astronomer John Bevis (1695-1771) but it was named in 1848 by William Parsons (1800-1867), third Earl of Rosse, who thought it resembled a crab's claw when he saw it through his 72-inch telescope at Birr Castle in Ireland.
At 0541 UT on August 27th the distance between the Earth and Mars is the same as that between the Sun and Mars, at 1.4586 AU (218.2 million kms or 135.6 million miles). Seen from a point far above the Earth's North pole, the Earth, Mars and the Sun now appear to form an isoscelene triangle in space, with Mars positioned at the apex.
On August 28th Mars passes 2°.0 North of the star Tianguan ( Tau or Zeta Tauri, mag. +2.9v), which marks the tip of the Bull's Southern horn. The name, adopted by the IAU in 2017, is derived from Chinese astronomy, in which the star is known as the Celestial Gate, part of an asterism contained within a mansion called Bì Xiù ('the Net').
At around 19 hours UT on August 29th Mars is positioned between the bright stars Capella and Betelgeuse ( Ori or Alpha Orionis, mag. +0.7v), the latter being an orange-red variable star at the North-eastern corner of Orion's quadrilateral. The two stars are separated in the night sky by a little under 40°, Mars on this occasion being 16°.2 to the NNW of Betelgeuse and 23°.2 SSE of Capella.
Mars passes 16°.1 North of Betelgeuse on September 3rd; at magnitude +0.7 the Red Planet shines at nearly the same brightness as the red giant star. The Red Planet passes North of Orion's club, topped by the stars Chi-1 Orionis (1 Ori, mag. +4.4) and Chi-2 Orionis (2 Ori, mag. +4.6), between September 3rd and 6th.
A High Mountain in the Tharsis region of Mars (lower left of centre) appears prominent near the planet's terminator as it casts a late-afternoon shadow on to the Martian surface; such effects are notable in large telescopes when Mars is near quadrature (click on the thumbnail for a larger version). This image was captured by John Sussenbach (Houten, Netherlands) in August 2022 using a 355 mm (14-inch) SCT telescope fitted with a CMOS camera (Image: John Sussenbach / ALPO-Japan)
Mars crosses to the North of the ecliptic at 02 hours UT on September 6th, entering Gemini, the Twins, at around 15 hours UT that same day. The planet passes 11' (0°.18) North of the star 1 Gem (1 Geminorum, mag. +4.2), at the Western end of the constellation, at 2305 UT.
A short distance North-east of 1 Geminorum is the open star cluster M35 (NGC 2168). The cluster has an apparent diameter of 30' (about the apparent size of the Full Moon) and contains over 400 stars(!) It can be glimpsed with the naked-eye as a misty patch of light on a dark, clear night. Mars passes around 50' (0°.83) South of the cluster between 07 hours UT on the 8th and 07 hours UT on the 9th.
Mars passes 1°.0 North of Propus ( Gem or Eta Geminorum, mag. +3.5v), also referred to as Tejat Prior before IAU standardization, on September 11th.
On September 16th Mars attains 7" in apparent diameter; which is considered large enough for serious amateur observers to begin resolving detail in the planet's surface (pending seeing conditions). On the same day the planet passes 1°.0 North of the star Tejat ( Gem or Mu Geminorum, mag. +3.0v), which together with Propus marks the Northern twin's lower left leg. Before IAU standardization the star was known by the name of Tejat Posterior, among others.
At around 0325 UT on September 17th binocular or telescopic observers located in the Southern half of South Africa are able to observe Mars occulting the faint variable star NW Gem (NW Geminorum, mag. +8.0), designated TYC 1879−00828−1 in the Tycho-2 catalogue. The star disappears from view in the vicinity of the planet's Northern pole, re-appearing up to 5 minutes later. For a detailed finder chart and a visibility map visit the Belgian VVS website.
On September 20th the planet passes 7°.1 North of Alhena ( Gem or Gamma Geminorum, mag. +1.9), at the ankle of the Southern Twin's left leg. On September 22nd Mars passes 1°.7 South of Mebsuta ( Gem or Epsilon Geminorum, mag. +3.0), a yellow supergiant double star positioned at the 'groin' of the Northern Twin (Castor).
Mars attains its minimum phase for the apparition, at 87.4%, on September 27th, causing the planet to appear noticeably gibbous when seen through telescopes. The Red Planet now shines at magnitude +0.5, technically making it a zeroth-magnitude object, its apparent diameter being 7".4 and its solar elongation 82º West.
At around 09 hours UT on September 27th Mars forms an isosceles triangle with Gemini's two luminaries Castor ( Gem or Alpha Geminorum, mag. +1.6) and Pollux ( Gem or Beta Geminorum, mag. +1.1), Mars being positioned at the apex. The long sides of the triangle measure 12°.3 and the angular distance of the short side (from Castor to Pollux) is 4°.5. Mars shines conspicuously brighter than both stars at this time. The temporary celestial triangle points South-westwards towards Bellatrix in Northern Orion. The three celestial bodies will form another isosceles triangle in five months' time, when Mars is past its peak brightness.
On September 30th Mars passes 1°.0 South of Gem (Omega Geminorum, mag. +5.2), which is positioned roughly at the centre of the constellation.
On October 1st Mars passes 2°.6 North of the variable and optical double star Mekbuda (Gem or Zeta Geminorum, mag. +3.9v), which is positioned at the upper left leg of the Southern Twin (Pollux).
On October 4th Mars passes 7°.1 South of the star Gem (Tau Geminorum, mag. +4.4), located in the upper torso region of the Northern Twin. In 2013 the star was found to be hosting an exoplanet, named Tau Geminorum b. Some 370 light years distant, it has a mass equivalent to 20½ Jupiters and it orbits the star at a local distance of 1.17 AU in a period of 306 days.
At around 1116 UT on October 7th Mars occults the magnitude +9.8 star TYC 1909−00533−1, an event visible using optical aid in twilight/darkness from the Southern USA (the Gulf Coast, Florida and Southern Texas), Mexico, Central America, the Western Caribbean and the South-eastern Pacific Ocean. For a detailed finder chart and a visibility map visit the Belgian VVS website.
Mars passes 54' (0°.9) North of the double star Wasat ( Gem or Delta Geminorum, mag. +3.5) at 08 hours UT on October 8th. It is one of several stars - some bright and some not - which the Red Planet will pass on three occasions over the course of the next 6¾ months.
Mars occults another faint star on October 10th. At around 0140 UT it passes in front of the star TYC 1909−01141−1 (mag. +8.9), an event visible in twilight/darkness from Europe (except the South-west, the far West and far South), Greenland and Western Russia. The star disappears behind the planet's bright Eastern limb and re-appears, up to 6½ minutes later, from behind its dark Western limb. See the VVS website for a visibility map and timings.
Mars passes 5°.0 South of Gem (Iota Geminorum, mag. +3.8), located at the 'heart' of the twin Castor, on October 11th.
On October 12th the Red Planet passes 1°.7 North of the planetary nebula NGC 2392, the nebulous remnants of a red giant star which exploded at some time in the distant past. Through small telescopes it appears as a bright blue-green disk, some 48" across, with slightly fuzzy edges. The exploded star lingers on at the nebula's centre, shining at 10th-magnitude. In larger telescopes a dark ring can be seen surroundng the central disk, with more detail visible in the irregularly-bright outer ring. The nebula resembles a face wearing a fur parka, the central star marking the individual's nose. It was discovered in 1787 by astronomer and musician Sir William Herschel (1738-1822) who, six years earlier, had discovered Uranus. NGC 2392 is about 6,500 light years from Earth.
Mars reaches Western quadrature at 0829 UT on October 14th, when it is positioned 90° West of the Sun. The planet now shows an illuminated phase of 87.7%, fractionally larger than it showed at minimum phase on September 27th. If the orbit of Mars was perfectly circular, the quadrature and minimum phase dates would always coincide, however since the planet's orbit is eccentric, they often do not. At Western quadrature Mars is rising almost 10 hours before sunrise at latitude 60° North, 7 hours before sunrise at 30° North, 5 hours before the Sun at 15° South and 3½ hours before the Sun at 45° South. Directionally, Mars rises towards the North-east at higher Northern latitudes and towards the ENE at latitudes further South. At latitudes North of about 44° North, the planet has already crossed the local meridian as it disappears from view in the dawn twilight; to the South of this latitude it has not yet crossed the local meridian when it disappears from view.
Mars at Minimum Western Phase imaged by Mike Hood (Kathleen, GA, USA) in August 2022 using a 200 mm (8-inch) apochromatic refracting telescope fitted with a CMOS camera (click on the thumbnail for a larger version). Mars showed an 84% illuminated phase and was 8".6 in apparent diameter (Image: Mike Hood / ALPO-Japan)
On October 15th Mars passes 9°.2 South of Gemini's second-brightest star Castor, then 4°.3 South of Gem (Upsilon Geminorum, mag. +4.0), at the 'heart' of the twin Pollux, on October 16th.
On October 18th the planet passes 12°.0 South of another star whose 'new' name was formally recognised by the IAU in 2017. Jishui ( Gem or Omicron Geminorum, mag. +4.9) is positioned close to the constellation's Northern border with Lynx. The name comes from ancient Chinese astronomy, Jishui being the water flow from the River Beihe which was used for wine-making and brewing. In the Chinese night sky the river was identified with the stars Castor, Pollux and nearby Gem (Rho Geminorum, mag. +4.2).
On October 20th at 13 hours UT Mars (mag. +0.2), the star Gem (Kappa Geminorum, mag. +3.5) and Gemini's brightest star Pollux line up along 5°.6, aligned roughly NNE-SSW; the first of three occasions when these three celestial bodies will line up during this apparition. To the SSW the line is directed towards the bright star Procyon ( CMi or Alpha Canis Minoris, mag. +0.5) in the constellation of Canis Minor, the Lesser Dog, located some 17° to the South of Mars. Mars passes 2°.0 South of Gem itself a few hours later, then 5°.7 South of Pollux at 07 hours UT on the 21st. In 2006 an exoplanet was discovered orbiting Pollux. Named Pollux b or Thestias (after Greek and Roman mythology), it is about 34 light years away and has a mass of about two Jupiters. It orbits its parent star in a nearly circular orbit, at a local distance of 1.64 AU in a period of 1.6 years.
Mars enters Cancer, the Crab, at 20 hours UT on October 29th. Two hours later Castor, Pollux and Mars form a line 11°.4 long, orientated NNW-SSE, pointing Southwards through the South-western part of the constellation towards the head of Hydra, the Water Snake, which is positioned 20° away from Mars. Castor, Pollux and Mars will form a line on a further two occasions over the coming months.
Mars passes 53' (0°.88) South of the star 1 Cnc (Mu-1 Cancri, mag. +6.0), in Eastern Cancer, at 15 hours UT on November 2nd, then 7' (0°.11) North of 2 Cnc (Mu-2 Cancri, mag. +5.3) at 1405 UT on the 3rd. The Red Planet will pass 1 Cnc on a second occasion next January before having a very close pass of the star in the following April.
At 13 hours UT on November 3rd Mars is positioned at precisely 1.0000 AU from the Earth, i.e. the same distance as the average distance of the Earth from the Sun (149.6 million kms or 92.9 million statute miles). Viewed from a point in space far above the Earth's North pole, the Earth, Mars and the Sun would now appear to form an isosceles triangle, with Earth positioned at the apex. The distance between Earth and Mars is currently decreasing at a rate of about 1.1 million kms (683,400 statute miles) per day.
Mars reaches magnitude +0.0 on November 6th. On November 9th Mars passes 12°.3 North of Cancer's brightest star Tarf ( Cnc or Beta Cancri, mag. +3.5), at the South-western corner of the constellation's lambda-shaped () figure. Prior to IAU standardisation in 2018 it was known by the name Altarf, which is Arabic for 'the End', i.e. the end of the Crab's leg. An exoplanet was detected orbiting Tarf in 2014. Designated Beta Cancri b, it is almost 300 light years distant and has a mass of almost eight Jupiters. It orbits Tarf in a period of 1.7 years at a local distance of 1.7 AU.
On November 12th, Mars reaches 10".0 in angular diameter, positioned about 107° West of the Sun. The planet is now brightening significantly with each passing week, its pale orange coloration seemingly more obvious than in the preceding months. For telescopic observers, the planet is now at a sufficiently large apparent size for significant surface detail to be seen and for a regular observing campaign to begin. On this same day Mars passes the position in its orbit which marks the Spring Equinox in its Northern hemisphere (Autumnal Equinox in its Southern hemisphere). For a diagram of how the Martian seasons compare with those of the Earth, see the Martian seasons page.
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At 09 hrs UT on November 13th Mars passes 2°.6 South of Piautos ( Cnc or Lambda Cancri, mag. +5.9), a star which is on the threshold of naked-eye visibility under typical dark skies. Formally named by the IAU in 2018, Piautos ('the Eye') formed part of a lunar asterism in Coptic astronomy.
By the third week of November Mars' apparent motion against the background stars is gently drifting Northwards, taking the planet further away from the ecliptic. Its rate of motion against the background stars has halved in recent weeks, from 0º.4 per day in late October to just 0º.2 per day by the third week of November. Its apparent motion will cease completely when it reaches its Eastern stationary point in a couple of weeks' time.
On November 19th at around 0248 UT the Red Planet occults a magnitude +9.1 star in central Cancer. Star TYC 1391−00847−1 disappears behind Mars' bright Eastern limb and, up to 19½ minutes later, re-emerges from behind its dark Western limb. The event is visible in twilight/darkness from Southern Europe, the Middle East, Africa (except the far South), Eastern Brazil and the central Atlantic Ocean (see the VVS website for a visibility map and timings). Note how the planet's slowing apparent motion has caused this occultation to last considerably longer than the five which have preceeded it thus far in 2024.
At 0415 UT on November 27th Mars passes 50' (0°.83) North of the fifth-magnitude star Cnc (Eta Cancri, mag. +5.3).
Mars reaches magnitude -0.5 on December 1st, meaning that it now shines at minus first magnitude.
At around 2222 UT on December 2nd Mars occults its final faint star (i.e. of between 8th and 10th magnitude) of 2024. The star TYC 1398−00878−1 (mag. +8.9) disappears behind Mars' bright Eastern limb and re-emerges from behind its dark Western limb. Since the planet is less than a week away from its stationary point and is therefore moving against the background stars very slowly, the event lasts up to 1 hour and 8 minutes. It is visible in darkness from Greenland, Iceland, the UK (except the far East and South-east), Ireland, South-western Norway and the Western extremity of France. Observers located in Western Bretagne (France), parts of East and South-east England (UK) and Vestlandet (Norway) see a grazing occultation of the star by Mars' Southern limb. A visibility map and timings of the event can be seen at the VVS website.
At 2047 UT on December 7th Mars' Eastward motion ceases as the planet reaches its Eastern stationary point, positioned 1°.3 North-east of Cnc and 1°.7 West of the star Asellus Borealis ( Cnc or Gamma Cancri, mag. +4.6) in central Cancer. Over the next few days its apparent motion changes direction from Northwards to North-westwards as the planet turns retrograde - a motion which will continue for the next 2½ months.
By mid-December Mars is crossing the local meridian in darkness from across the inhabited world. Having reversed its motion against the background stars, the planet begins to pass several of the brighter celestial bodies that it had passed over the previous two months, but in reverse order.
Moving North-westwards, Mars passes to the North of Cnc for the second time at 0347 UT on December 18th, this time at an angular distance of 1°.8, about 1° further away than it had passed the star three weeks earlier.
From around 08 hours UT on December 18th Mars is involved in the second lunar occultation of the planet's apparition, when the 17-day-old waning gibbous Moon passes in front of the Red Planet. The visibility path passes over the Earth's North Pole, the event being seen in darkness from several hyperborean regions: the Bering Sea, the Arctic Ocean, North-eastern Russia, Northern Alaska, Arctica and Northern Canada (Victoria Island, Queen Elizabeth Island and Baffin Island). It is visible in twilight/darkness from Newfoundland & Labrador and Greenland and fully in twilight from Iceland and the extreme North-western Atlantic Ocean. The planet disappears behind the Moon's bright Eastern limb and re-appears from behind its dark Western limb. For a map and timings of this event, follow the link provided in the Moon near Mars section below.
Mars reaches magnitude -1.0 on December 22nd. On December 30th the planet passes Piautos for a second time, on this occasion passing 31' (0°.51) to the South of the star at 20 hours UT. This is 2° closer to the star than it was at its last pass in mid-November.
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Now moving WNW against the background stars, Mars passes Tarf for the second time on January 2nd, on this occasion at a distance of 14°.7, some 2°.4 further North of the star than at its previous passage in early November.
Mars passes 2°.8 North of 2 Cnc at 11 hours UT on January 8th, then 1°.9 North of 1 Cnc at 08 hours UT on the 9th - some 2°.7 further North than at its previous passages of these stars in early November.
At 1332 UT on January 12th Mars reaches its closest point to the Earth for this apparition, at 0.6423 AU distant (96.1 million kms or 59.7 million miles), a point known as the perigee (or, in the specific case of Mars, the periareion). The Red Planet now shines at magnitude -1.36 and its apparent size is 14".57 (its largest for the apparition). This is double the size that it was in late September 2024 and triple the size that it was in mid-May of that year. At the moment of closest approach the planet is positioned only 6' (0°.1) away from Cancer's western border with Gemini, which it re-enters at 20 hours UT on the same day.
From around 01 hours UT on January 14th the Full Moon passes in front of Mars in the third lunar occultation of the apparition. The event is visible in darkness from central and Eastern USA, North-eastern Mexico, Southern and Eastern Canada, the Northern Caribbean, the central Atlantic Ocean and North-western Africa. It is visible in twilight/darkness from Western USA, North-western Mexico and central Western Africa. For a map and timings of this event, follow the link provided in the Moon near Mars section below.
Mars reaches opposition to the Sun at 0154 UT on January 16th in Eastern Gemini, positioned only 1°.2 away from the constellation's Eastern border with Cancer and 3°.5 South-east of Pollux (indeed, Castor and Pollux very nearly 'point the way' to Mars in the night sky). The planet is now directly opposite the Sun in the sky (solar elongation = 180°), its illuminated phase is 100% and it shines at magnitude -1.38 (its brightest for the apparition). Mars is now the fifth brightest object in the night sky, after the Moon, Venus, Jupiter and Sirius ( CMa or Alpha Canis Majoris, mag. -1.4). Due to the eccentricity of Mars' orbit, its apparent disk size is not quite as large as it was at its closest passage just a few days earlier: lying at a distance of 0.6436 AU from the Earth, Mars is now about 204,665 kms (127,170 miles) more distant than it was at perigee. Consequently its apparent size is fractionally smaller, at 14".54. On opposition day Mars is moving slightly North of Westwards at a rate of about 0º.4 per day.
Mars at Opposition on December 8th 2022 (left) sketched by Paul G Abel (Leicester, UK) and (right) imaged by Johnson Lo (Hong Kong) (click on each thumbnail for its larger version). Abel used a 305 mm (12-inch) Newtonian reflector telescope at 320x and 300x magnifications in his 'longest ever Mars observing session', in which he produced six individual sketches over the course of nine hours. Lo used a 355 mm (14-inch) Dobsonian telescope fitted with a planetary & guiding camera. Due to the widely different locations and observing times of each observer within the same day, each image shows an opposite side of the planet (note that South is up in Abel's sketch but North is up in Lo's image) (Images: Paul G Abel / Johnson Lo / ALPO-Japan)
At opposition, a superior planet (such as Mars) rises around sunset, is visible throughout the night and sets around sunrise. Its highest point in the sky is reached when it crosses (transits) the observer's meridian at local midnight (due South at midnight in the Northern hemisphere; due North at midnight in the Southern hemisphere). At the 2025 opposition Mars has a declination of +25°.1; as such, the current opposition favours Northern hemisphere observers, where Mars transits the meridian at a high altitude (at latitude 25º 6' North the planet transits at the zenith, directly above the observer's head). A list of meridian transit altitudes and directions of the planet at opposition for various latitudes over several Martian oppositions is given in the table below.
On opposition day, Mars is experiencing Spring in its Northern hemisphere and Autumn in its Southern hemisphere (having had its Northern hemisphere Spring equinox in the previous November). The planet's Northern Pole is tipped towards the Earth at an angle of about 10º (DE = +10º), giving us a shallow view of its Northern Polar Cap (NPC). Mars is positioned at a heliocentric longitude of 115º.8 ( = 115°.8) and the areocentric longitude of the Sun (Ls) is 30°.8. The Martian Year is 38, the Martian Month is 2 and opposition day equates to Sol Number 63 on Mars. The equivalent Earth date on Mars - called the Martian Date (MD) - is April 21st. All the terms given in this paragraph are explained in more detail on the Martian seasons page.
At the 2025 opposition, Mars is 0.4 magnitudes dimmer than when it previously reached opposition in December 2022 and its apparent disk diameter is about 15% smaller. Nonetheless it is the largest apparent disk size that the planet will show to the Earth before the year 2031. Mars is currently in a period of aphelic oppositions (where the planet is close to the aphelion point of its orbit) and in 2025 is much closer to its aphelion than it was in 2022 but further from it than it will be in 2027 (for more details, see the Mars oppositions page).
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At 16 hours UT on January 17th Castor and Pollux again 'point the way' to a bright Mars in the night sky, the three celestial bodies forming a line 7°.5 long, Mars itself being located 3° to the SSE of Pollux.
Mars passes to the South of Pollux for a second time at 17 hours UT on January 21st, on this occasion moving retrograde and 2°.4 South of the star. The planet then passes 1°.2 North of Gem at 06 hours UT on the 22nd; in both cases Mars is 3°.3 further North of the star than on the planet's first passage in the previous October.
Pollux, Mars and Gem form a line 3°.6 long at 02 hours UT on January 22nd, the Red Planet positioned between the two, being 2°.3 South of Pollux and 1°.3 North of Gem.
Opposition day having passed, Mars' solar elongation changes from Westerly to Easterly and the angle reduces below 180°. By January 23rd - one week after opposition - the planet's solar elongation has reduced to 169° East of the Sun. On this day Mars attains its maximum ecliptic latitude of the 2024-25 apparition, when = +4°.3 (i.e., 4°.3 North of the ecliptic). This should not be confused with the planet's most Northerly declination, which will be reached on February 10th. Ecliptic latitude (symbol ) is measured in relation to the ecliptic plane (the apparent path of the Sun through the zodiac, which is also the plane of the Earth's orbit in space). The ecliptic itself has a latitude of 0° ( = 0°); latitudes to the North of it are measured positive (+) and those to the South of it are measured negative (-). Declination, on the other hand, is measured in relation to the celestial equator, which is the 0° latitude of Earth projected from the Earth's centre into space; declinations are likewise measured positive and negative in relation to it. The two planes (ecliptical and equatorial) are inclined at 23°.4 to each other, caused by the tilt of the Earth's axis in space.
Mars continues its retrograde motion, passing the following stars for the second time in this apparition, some 3°.4 further North than at their previous passages: 8°.7 South of Jishui ( Gem) on January 25th; 55' (0°.91) South of Gem at 15 hours UT on January 27th; 5°.8 South of Castor on January 28th and 1°.5 South of Gem on February 4th. By the time the planet passes 4°.3 North of Wasat on February 9th it has returned to a due Westward motion against the background stars.
From around 1830 UT on February 9th Mars is involved in the fourth lunar occultation of the apparition, when the 11-day-old waxing gibbous Moon passes in front of the planet, the latter disappearing behind the Moon's dark Eastern limb and re-appearing from behind its bright Western limb. The event is visible in darkness from Northern Scotland (Northern Orkney Islands, Shetland Islands), Svalbard, Northern Scandinavia, Russia, Mongolia, the Korean peninsula and China. It is seen in continuous twilight from Northern and Eastern Greenland, Arctica and Iceland. Follow the link below for a map and timings of the event.
A Lunar Occultation of Mars sketched by Chris Nuttall (York, UK) on the day of the planet's opposition on December 8th 2022 (click on the thumbnail for a larger version). Mars was about to disappear behind the Moon's Eastern limb; it re-appeared from behind the Western limb one hour later. Nuttall used a 300 mm (12-inch) Newtonian reflector telescope at 512x and 300x magnifications (Image: Chris Nuttall / ALPO-Japan)
At 1608 UT on February 10th Mars attains its most Northerly declination for this apparition ( = +26° 13' 58" or +26°.2327 in decimal form), the most Northerly declination attained by the planet since January 2008 and before January 2040. Mars now sets at its most Northerly point along the local horizon, the actual point of setting depending upon the observer's latitude. This will be towards the NNW at high-Northern latitudes, the North-west at mid-Northern and mid-Southern latitudes and towards the WNW at most other inhabited latitudes. Mars is now setting 15 hours after the Sun at latitude 60° North (from where its sets in twilight), 12 hours after the Sun at 40° North, 9¾ hours after sunset at the Equator and 6¾ hours after sunset at 45° South.
By the middle of February Mars is setting in darkness from all except higher Northern latitudes. Its motion against the background stars begins to turn Southward from around this time, the planet rapidly slowing and reaching its Western stationary point in central Gemini at 09:34 UT on February 24th. The Red Planet is positioned 7°.3 South-west of Castor and 7°.2 WSW of Pollux, thus forming a near-isosceles triangle with the two stars. Its motion then turns direct once more, as it will continue to do so for the remainder of the apparition.
By the third week of February Mars has faded back to magnitude -0.5 ('zeroth magnitude') and its apparent diameter has reduced to 11".7 - some 80% of the size that the planet had appeared at its closest approach back in mid-January. By March 10th the apparent size of the Martian disk has fallen below 10", its brightness fading still further to 0.0 within a couple of days.
Now moving towards the ESE, Mars begins to pass the numerous stars which it has already passed on two occasions before, starting on March 11th when it passes 3°.4 North of Wasat, almost a degree further South than on its previous passage.
In the midnight hour UT on March 17th Mars is again positioned at precisely 1.0000 AU from the Earth, i.e. the same distance as the average distance of the Earth from the Sun (149.6 million kms or 92.9 million statute miles). When the planet was last 1.0000 AU from Earth in the previous November its distance from Earth was slowly reducing; now the planet's distance is slowly increasing. As was the situation 4½ months earlier, when viewed from a point in space far above the Earth's North pole, the Earth, Mars and the Sun would again appear to form an isosceles triangle, with Earth positioned at the apex.
During the final two weeks of March, Mars passes the following stars which it had previously passed twice before: 2°.7 South of Gem on March 18th; 7°.3 South of Castor on March 26th; 2°.4 South of Gem on March 27th and 10°.2 South of Jishui ( Gem) on March 30th. Mars is around 1°.5 further South than on its previous passage of these stars in late January and early February.
By early April Mars' apparent magnitude has faded to +0.5 ('first magnitude'). At 1130 UT on April 2nd Mars, Gem and Pollux line up for the third and final time in this apparition, this time along 4°.0, on a NNE-SSW orientation. At 12 hours UT on the same day the planet passes 27' (0°.45) to the South of Gem, then 4°.1 South of Pollux on April 3rd; these are about 1°.7 further South than on their previous passes in mid-January.
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On April 11th at 0330 UT Castor, Pollux and Mars line-up for the third and final time in this apparition, this time along 10°.0. The apparent distance between Mars and Pollux (5°.5) is only 1° longer than that between Castor and Pollux.
Mars re-enters Cancer at 21 hours UT on April 12th. At 1018 UT on April 16th the planet passes just 1' (0°.016) South of 1 Cnc - an angular distance which is equivalent to only eight apparent Mars diameters. The planet reaches aphelion (its most distant orbital position from the Sun) on the same day, when it is positioned at a solar distance of 1.6660 AU (249.2 million kms or 154.8 million miles). Following its very close pass of 1 Cnc, Mars passes 57' (0°.9) North of 2 Cnc at 06 hours UT on April 17th; its passage of the Mu Cancri stars has been some 1°.9 further South than at its previous (retrograde) passes of these stars in early January.
Mars reaches Eastern quadrature - when it is positioned 90° East of the Sun - on April 21st. The planet now shows an 89.9% illuminated phase and shines at magnitude +0.8. Unlike at Western quadrature, the illuminated part of the planet's disk faces Westwards (not Eastwards, as before) because it is now positioned to the East of the Sun when seen from the Earth. Mars now sets 7½ hours after the Sun at latitude 60° North, 6½ hours after the Sun at 30° North, 6 hours after sunset at 15° South and 5½ hours after sunset at 45° South. Directionally it sets in the North-west from mid and high-Northern latitudes and in the WNW from latitudes further South. At latitudes North of about 4° South the planet has already crossed the local meridian as it appears into view in the dusk twilight; to the South of this latitude it has not yet crossed the local meridian when it comes into view.
On April 22nd Mars passes North of Tarf for the third and final time for this apparition, on this occasion at a distance of 12°.8, some 1°.9 further South of the star than at its previous pass at the beginning of January. On the following day Mars falls below 7" in diameter, essentially meaning that detail on the planet's surface is now rather too indistinct for continued serious telescopic observation. On April 24th the planet passes 2°.3 South of Piautos for a third and final time in this apparition, this being about 1°.8 further South than on its previous pass.
On April 25th Mars attains its minimal illuminated phase for the Eastern elongation period of the apparition, at 89.8%. Unlike the planet's Western elongation period in 2024, when the minimum phase and quadrature dates were separated by a few weeks, on this occasion minimum phase falls only four days after the planet attains quadrature. Note that this is not the minimum phase for the whole apparition - this took place in the previous September, when the phase was 2.4% smaller.
Now in central Cancer, Mars passes 26' (0°.43) North of Cnc at 0310 UT on May 1st, this being the last of the brighter stars which the planet passed whilst describing its apparent loop during the 2024-25 apparition. As the Red Planet accelerates out of the loop at a rate of 0°.46 per day, it leaves behind it the ghost of an apparent loop on the Gemini-Cancer border which measured 19° in apparent diameter and 1°.8 in apparent height.
Mars at Minimum Eastern Phase imaged by Gary Walker (Georgia, USA) in March 2023 during the planet's evening sky appearance (click on the thumbnail for a larger version). Walker used a 254 mm (10-inch) Maksutov-Cassegrain catadioptric telescope fitted with a planetary & guiding camera. He noted an 'apparent bright cloud condensation' over the Hellas region (at upper left of disk). The planet was 89% illuminated and 7".2 in apparent diameter (Image: Gary Walker / ALPO-Japan)
Between 05 hours UT on May 4th and 09 hours UT on May 6th Mars, now magnitude +1.0, passes to the North of the star cluster Praesepe, also known as the Beehive Cluster (M44 or NGC 2632). Under dark, rural skies it is visible to the naked-eye as a hazy patch of light and in city locations it is easily seen in binoculars. 'Praesepe' is a Latin word meaning 'manger', named after the Nativity story in the Christian Bible (another, less commonly used name for the cluster is the Manger). Mars passes 0°.6 North of the cluster's centre at around 06 hours UT on the 5th.
Also present in the Nativity story were two donkeys, and they are represented in the night sky by two fourth-magnitude stars: the aforementioned Asellus Borealis, the Northern donkey, and Asellus Australis ( Cnc or Delta Cancri, mag. +3.9), the Southern donkey. The two stars are separated in the night sky by 3º.3 and they flank the Praesepe cluster on its Eastern side. Mars passes 1°.3 South of Asellus Borealis at around 16 hours UT on May 6th and 1°.8 North of Asellus Australis at around 09 hours UT on May 7th. The planet passes between the two stars at about 2335 UT on May 6th.
Mars passes 8°.8 South of Cnc (Iota Cancri, mag. +4.0), at the top of the constellation's lambda-shaped figure, on May 8th. On May 14th the planet passes 7º.1 North of Acubens ( Cnc or Alpha Cancri, mag. +4.3), a double star positioned towards the South-eastern corner of the constellation.
At 0115 UT on May 19th Mars passes 3°.9 South of Nahn ( Cnc or Xi Cancri, mag. +5.7), a star close to the naked-eye threshold which was 'newly-named' by the IAU in 2018. Nahn ('the Nose') formed part of a lunar asterism in Persian astronomy.
Mars enters Leo, the Lion, in the midnight hour (UT) of May 26th. At 1314 UT on May 27th the distance between the Earth and Mars is the same as that between the Sun and Mars, at 1.6579 AU (248 million kms or 154.1 million miles). The configuration resembles that which took place in August of the previous year, although the Earth-Mars distance is greater on this occasion. Seen from far above the Earth's North pole, the Earth, Mars and the Sun again appear to form an isoscelene triangle in space, with Mars positioned at the apex.
On May 30th Mars passes 6°.7 South of the star Alterf ( Leo or Lambda Leonis, mag. +4.3), which is positioned at the 'jaw' of the Lion's head.
On June 4th Mars passes 5°.5 North of the star Subra ( Leo or Omicron Leonis, mag. +3.5), positioned at the fore-leg of the Lion, although the name is Arabic for a mane or shoulder. From June 6th through to the 22nd the planet passes to the South of the Sickle of Leo, at the Western end of the constellation (it forms the head and chest of the Lion); to the naked-eye it appears as a backward question-mark (). The passsage of the Sickle begins on June 6th as Mars passes 8°.8 South of the star Ras Elased Australis, also known as Algenubi ( Leo or Epsilon Leonis, mag. +2.9), at the upper North-western end ('pointed end') of the sickle.
Mars passes 11°.6 South of the star Rasalas ( Leo or Mu Leonis, mag. +3.9), at the top of the sickle, on June 9th. An exoplanet (Mu Leonis b) was discovered orbiting the star in 2014. Located 106 light years away, it has a mass equivalent to just under 2½ Jupiters and it orbits Rasalas at a local distance of 1.1 AU in a period of 358 days.
By mid-June, observers at high-Northern latitudes lose sight of Mars as it slips into the summer dusk twilight. Observers here will not see the planet by naked-eye again for another thirteen months, when it begins its 2026-28 apparition. Slightly further South, observers at mid-Northern latitudes have a further two months in which to view the planet.
Mars passes 47' (0°.78) North of Leo's brightest star Regulus ( Leo or Alpha Leonis, mag. +1.4), positioned at the base of the Sickle, at 0425 UT on June 17th. The Eastern end of the Sickle is marked by the star Algieba (1 Leo or Gamma-1 Leonis, mag. +2.3), which is at the base of the Lion's neck (although the name is Arabic for 'the forehead'). It is a double star with golden-yellow components (1 Leo and 2 Leo) of magnitudes +2.3 and +3.6, separated by an angular distance of 4".7. Mars passes 8°.2 South of the star - thus completing its passage of the Sickle - on June 22nd. In 2009 an exoplanet (Gamma-1 Leonis b) was discovered orbiting Algieba, which is 130 light years distant. The exoplanet has a mass equivalent to 8¾ Jupiters and it orbits Algieba at a local distance of 1.2 AU in a period of 428 days.
At 1435 UT on June 28th Mars passes 58' (0°.96) North of Leo (Rho Leonis, mag. +3.8).
On June 30th another lunar occultation of Mars takes place, the penultimate of the planet's 2024-25 apparition. From around 0140 UT the four-day-old waxing crescent Moon occults the planet, the event being visible in darkness from the South-eastern Pacific Ocean and North-eastern South America (South-western Colombia, Ecuador, Northern Peru). It is seen in continuous twilight from the central Pacific Ocean. For a map and approximate timings of the event, follow the link below.
By July 3rd Mars' apparent magnitude has fallen to +1.5, thus returning it to second magnitude, which it will continue to be through to late October. The planet is now 58° East of the Sun (and reducing), its apparent diameter is just below 5" (and reducing) and its illuminated phase is about 92% (and increasing).
At 1035 UT on July 13th Mars passes 31' (0°.51) South of Leo (Chi Leonis, mag. +4.6), a variable and double star. In October 2015 the planet occulted the star in the morning sky, extinguishing it from view for up to 2½ minutes, when Jupiter was located only 0°.5 to the planet's WSW.
On July 17th Mars passes 9°.6 South of the star Chertan ( Leo or Theta Leonis, mag. +3.3), at the top of the Lion's rear leg. Prior to IAU standardisation in 2016 the star was also known as Coxa or Chort. At the same moment the planet passes 14°.6 South of the star Zosma ( Leo or Delta Leonis, mag. +2.7), at the rump of the Lion.
On July 20th, Mars passes 1°.0 South of Leo (Sigma Leonis, mag. +4.0), which is positioned at the rear 'paw' of the Lion.
Mars leaves the star chart coverage (above) on July 22nd. Later on the same day the planet passes 5°.8 South of Leo (Iota Leonis, mag. +4.0), positioned at the joint of the Lion's rear leg.
On July 27th Mars passes 4°.0 North of the star Leo (Upsilon Leonis, mag. +4.3), which is located only 7' (0°.11) from Leo's South-eastern border with Virgo, the Maiden. The star, which is 172 light years away, has an exoplanet (Upsilon Leonis b) with a mass equivalent to that of one-half Jupiter. It orbits the star at a local distance of 1.2 AU over a period of 385 days.
Mars enters Virgo at 03 hours UT on July 28th; over the next month the constellation is setting in the West at dusk and is best seen from latitudes South of the Northern Tropics. From around 1830 UT on the same day Mars is occulted by the waxing crescent Moon for the sixth and final occasion of the planet's apparition, an event which is seen in twilight from a small region of Antarctica (Getz Ice Shelf, Executive Committee Range). To see a map and approximate timings of the event, follow the link below.
Mars passes just 7' (0º.11) South of Zavijava ( Vir or Beta Virginis, mag. +3.6), at the back of the Maiden's head, at 0121 UT on August 3rd. Before IAU standardization Zavijava was also known by the names Zavijah, Zavyava or Alaraph.
On August 8th Mars crosses to the South of the celestial equator. With its declination being around 0º ( = 0º) the planet now sets due West across the inhabited world.
From the second week of August observers at around 50° North latitude begin to lose sight of Mars as it heads into the dusk twilight.
Mars passes 1º.0 South of the star Zaniah ( Vir or Eta Virginis, mag. +3.8), in central Western Virgo, at 21 hours UT on August 15th.
On August 24th Mars passes 4°.1 North of Vir (Chi Virginis, mag. +4.6), a star which was found to have an exoplanet (HD 110014 b) in 2009. It is thought to have a mass equivalent to eleven Jupiters, orbiting Chi Virginis at a distance of 2.1 AU in a period of 2.3 years.
Table showing the position and apparent magnitude of Mars for the latter part of the 2024-25 apparition (click on the thumbnail for the full-size table). As in the first table, the magnitudes, diameters and solar elongations refer to the middle of the period in question.
During the third week of August Mars attains it dimmest magnitude of the 2024-25 apparition (-1.61), the planet being just 4".2 in apparent diameter and showing an illuminated phase of 96%. Although Mars will continue to reduce in apparent size through to the end of the apparition, it will brighten slightly over that period because of its increasing phase.
On August 25th Mars passes 2º.6 South of the double star Porrima ( Vir or Gamma Virginis, mag. +3.5), named after one of the Roman goddesses of prophecy. Prior to IAU standardisation in 2016 was sometimes known by the name of Arich.
On August 31st Mars passes 8°.9 South of Minelauva ( Vir or Delta Virginis, mag. +3.4), a star which, prior to IAU standardisation in 2017, was sometimes known by its shortened name Auva.
Mars passes 1º.6 to the South of the double star Vir (Theta Virginis, mag. +4.4), in central Virgo, on September 6th.
Having passed its dimmest magnitude of the apparition in late August, Mars slowly begins to brighten again. On September 9th the planet passes 10°.2 North of 61 Vir (61 Virginis, mag. +4.7), a star which, since 1996, has been found to have three exoplanets (61 Virginis b, c and d). At 28 light years distant, they are amongst the closest exoplanets which are currently known to exist. They orbit their parent star at a distance which would place them within the equivalent orbit of Venus in our own Solar System. All three are considered to be Neptune-like, having a mass of between 5 and 23 Earths and making one orbit of the star in 4 days, 38 days and 123 days, respectively.
Mars passes 2°.3 North of Virgo's brightest star Spica ( Vir or Alpha Virginis, mag. +1.0) on September 12th. It is a blue-white star which dominates the South-eastern region of the constellation. On the following day the planet passes 22°.9 South of the star 70 Virginis (mag. +4.9), which is located close to the constellation's Northern border with Coma Berenices (Berenice's Hair). An exoplanet (70 Virginis b) was detected orbiting the star in 1996. At 58 light years distant, it has a mass equivalent to 7½ Jupiters and it orbits its parent star at a distance of about 0.5 AU over a period of 117 days.
Mars passes 9°.1 South of Heze ( Vir or Zeta Virginis, mag. +3.5) on September 16th.
The Red Planet crosses to the South of the ecliptic on September 23rd, its solar elongation falling below 30º on the same day. From around this time observers at mid-Northern latitudes lose sight of Mars from the WSW sky as it heads into the bright dusk twilight.
On October 1st Mars passes 3°.2 South of the star Kang ( Vir or Kappa Virginis, mag. +4.2), which is located near the constellation's South-eastern border with Libra, the Balance. In Chinese astronomy Kang was a constellation and a name given to the second lunar mansion. The star was named by the IAU in 2017.
Mars enters Libra at around 10 hours UT on October 4th; at this time of year the constellation is difficult to view from the low-Northern hemisphere and is best seen, setting in the WSW after dusk, from South of the Equator. From around this time Mercury (mag. -0.3) emerges into the dusk sky for its third (and final) evening apparition of 2025; this particular Mercurian apparition can only be observed from latitudes South of the Northern Tropics. In the first half of October Mercury approaches Mars at a rate of about 0°.8 per day. As it emerges the planet is positioned in South-eastern Virgo, a few degrees East of Spica and about 11° to the WNW of Mars. At midnight UT, Mercury is 8°.7 to the WNW of the Red Planet on October 8th and 6°.4 to the WNW of it on the 11th. The planet shines at around magnitude -0.2 during this time. Mercury enters Libra at 14 hours UT on October 12th, 5°.3 to the West of Mars.
One of the last Images of Mars to be captured during its 2021-23 apparition was this one, in July 2023, by Mark Lonsdale (Midgard Observatory, Canberra, Australia) (click on the thumbnail for a larger version). Mars was 36° from the Sun and 4".0 in apparent diameter. Lonsdale used a 355 mm (14-inch) aplanatic SCT reflector telescope fitted with a CMOS camera (Image: Mark Lonsdale / ALPO-Japan)
At around 0345 UT on October 15th the Red Planet passes 34' (0°.56) South of the double star Zubenelgenubi (2 Lib or Alpha2 Librae, mag. +2.8), which on older star maps was depicted as the top of Scales' balancing point. The star comprises a blue-white component of magnitude +2.7 (2 Lib) and a white companion of magnitude +5.2 (1 Lib), separated in the night sky by a distance of 3'.8 and easily resolved in binoculars. On October 19th Mars passes 7º.6 North of the star Brachium ( Lib or Sigma Librae, mag. +3.3), the Southernmost star of the Scales' easily recognised quadrilateral figure.
Mars, Mercury (mag. -0.1) and Brachium line up along 7°.5 at 2250 UT on October 20th, with Mercury - the brightest of the three - being positioned in the centre. At 0616 UT on the following day Mercury passes a wide 2°.0 to the South of Mars in the penultimate planetary conjunction of the apparition, which is only observable from latitudes South of the low-Northern hemisphere (see the Planetary Conjunctions section for more details). Mercury's motion in relation to Mars has slowed to about 0°.5 per day as it heads towards its Eastern stationary point, which it will reach in three weeks' time.
By October 22nd Mars has brightened slightly to magnitude +1.5, thus returning it to 'first magnitude' status. From around this time observers at low-Northern latitudes (ca. 30° North) begin to lose sight of Mars from the WSW sky as it slips into the bright dusk twilight.
On October 24th Mars passes 9º.1 South of the star Zubeneschamali ( Lib or Beta Librae, mag. +2.5), the Northernmost star of Libra's quadrilateral figure.
Now only observable from South of the Northern Tropics, Mars' solar elongation falls below 20º on October 27th, the planet closing in on the Sun at a rate of 0º.3 per day. When it first becomes visible at dusk the planet stands just 8° above the WSW horizon at 20° North, 12° high at the Equator and 10° high at 45° South, setting between 1 hour (20º North) and 1¾ hours (45º South) after the Sun.
With its return to central Libra in late October, Mars has now completed a full circuit of the zodiac since passing through superior conjunction nearly two years earlier.
Mercury enters Scorpius at 12 hours UT on October 29th. It reaches its greatest Eastern elongation (23°.9 East of the Sun) later that same day, shining at magnitude -0.0 and positioned 5°.1 to the South-east of Mars.
On October 30th Mars passes 4°.8 South of the star Zubenelhakrabi ( Lib or Gamma Librae, mag. +3.9), the Easternmost star of Libra's quadrilateral figure. Before IAU standardisation in 2017 the name was alternatively spelled Zuben Elakrab.
Mars enters Scorpius at 23 hours UT on November 3rd, with Mercury (mag. +0.0) located 5°.7 away to its South-east.
Observers at Northern Tropical and mid-Southern latitudes lose sight of Mars from around the second week of November.
Mercury reaches its Eastern stationary point on November 9th, positioned 3°.5 to the South-east of Mars. Moving slowly Northwards, it then turns retrograde and heads towards the North-west, initially in the direction of the Red Planet, closing in on it at a rapid rate of 1°.1 per day. At 1840 UT on November 12th Mercury (mag. +1.2) passes 1°.3 to the South of Mars in the eighth and final planetary conjunction of the 2024-25 apparition. Now in the vicinity of the Scorpion's head, the two planets are moving in opposite directions as they pass each other; Mercury towards the North-west and Mars towards the ESE. This is a difficult conjunction to observe since the pair are only 15° away from the Sun, the event only being visible between about latitudes 6° North and 37° South (for further details of its observability see below). Within hours of the conjunction Mercury speeds on in the direction of the Sun, becoming lost from view in the dusk twilight.
Mars' solar elongation falls below 15º on November 14th, by which time observers at low-Southern latitudes have lost sight of the planet in the WSW sky at dusk. From mid-November observers at Equatorial and Southern Tropical latitudes are the last to bid farewell to the Red Planet as it disappears into the bright dusk twilight, bringing the 2024-25 apparition to a close.
Mars reaches its most distant point from Earth (known as the apogee or, in the case of Mars, the apoareion) for this apparition on November 30th, when it lies at a distance of 2.4239 AU (362.6 million kms or 225.3 million miles). Were it to be visible from Earth at this time, its magnitude would be +1.3 and its apparent size only 3".8.
Mars enters Sagittarius at 20 hours UT on December 10th.
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Mars reaches superior conjunction (passing behind the Sun as viewed from the Earth) in central Eastern Sagittarius on January 9th 2026, when it is 2.4038 AU (359.6 million kms or 223.4 million miles) from Earth. The planet remains out of view - lost in the solar glare - for a further two months as it continues its Eastward course on the far side of its orbit from the Earth. Mars becomes visible again in the Eastern sky at dawn from early March 2026, when it is first glimpsed from Southern Tropical latitudes. This heralds the start of the 2026-28 apparition, which will see Mars reach opposition in Leo in February 2027.
[Terms in yellow italics are explained in greater detail in an associated article describing planetary movements in the night sky.]
Mars Conjunctions with other Planets,
2024-2025
Viewed from the orbiting Earth, whenever two planets appear to pass each other in the night sky (a line-of-sight effect) the event is known as a planetary conjunction or appulse. Not all planetary conjunctions will be visible from the Earth, however, because many of them take place too close to the Sun. Furthermore, not all of them will be seen from across the world; the observers' latitude will affect the altitude (angle above the horizon) at which the two planets are seen at the time of the event, and the local season will affect the sky brightness at that particular time. A flat, unobstructed horizon will normally be required to observe most of them.
Alas, most conjunctions involving Mars are unspectacular to view because the planet is usually positioned far away from the Earth - and is therefore not particularly bright - whenever they take place. Those involving Venus will always take place at solar elongations of less than 47° from the Sun, whilst those involving Mercury will always be less than about 27° from the Sun. In both of these instances twilight is often a problem, the lighter sky diminishing the visual impact of the conjunction (Mars looking like an ordinary, pale-orange star). Mars' most spectacular conjunctions take place when it is within a few months of opposition - and therefore at its brightest - at which times they involve either Jupiter or Saturn; these events are however very rare. Most conjunctions between Mars and Jupiter (or Mars and Saturn) occur at elongations of less than 90°, when Mars is far from its brightest in any given apparition. The 2024-25 apparition has one favourable conjunction involving Jupiter, with Mars five months away from opposition. At a solar elongation of 65° it is observable from most of the inhabited world.
In the 2024-25 period there are eight observable planetary conjunctions of Mars, involving all of the other Solar System planets. Six take place in the morning sky and two in the evening sky. In all except one case their visibility favours Southern hemisphere observers.
The Mars-Jupiter conjunction of August 14th 2024 takes place in Taurus, making it more favourable to Northern hemisphere observers. At magnitude +0.8 Mars is brighter than at any other conjunction in the 2024-25 period. At magnitude -2.0, Jupiter shines thirteen times brighter than Mars and it consequently remains visible for a longer period of time in the dawn twilight. At latitude 60° North the pair reach a decent 36° above the ESE horizon as Mars disappears from view, whilst at 50° North they are 45° high, also in the ESE. At 30° North they 58° high in the Eastern sky at the Red Planet's disappearance whilst at the Equator they are 57° high in the North-east. South of the Equator the pair are positioned in the NNE at Mars' disappearance; at latitude 15° South they reach 46° above the horizon whilst at 45° South they are 22° above the horizon.
A morning conjunction between Mars and Saturn in Aquarius on April 11th 2024 is well-positioned for Southern hemisphere viewers. The pair are separated in the sky by 0°.5 (the apparent diameter of the Full Moon) and they shine at similar magnitudes (+0.9 and +1.1 respectively) which makes for a good opportunity to compare the subtle colours of the two planets by naked-eye or with binoculars. As Mars disappears from view in the dawn twilight the pair are positioned 20° high in the ESE in the Northern Tropics, 28° high in the East at the Equator, 31° high in the East at 25° South and 30° high in the ENE at 45° South. Before fading from view the planets are visible for around 40 minutes (at 25° North), 1¼ hours (Equator), 1¾ hours (25° South) and 2 hours (45° South).
A conjunction between Mars and Venus takes place on February 22nd 2024, Venus passing 38' (0°.63) to the North of the Red Planet in Western Capricornus. At the moment of conjunction Venus is moving against the background stars at a rate of 1°.2 per day whilst Mars is moving at only 0°.8 per day. At 30° North the pair rise in twilight 1¼ hours before the Sun, attaining an altitude of just 8° above the ESE horizon when Mars disappears from view, whilst at 20° North they rise 1½ hours before sunrise, reaching 13° high in the ESE at the Red Planet's disappearance. From the Equator they rise 1¾ hours before sunrise and reach 18° high in the ESE. Southern Tropical latitudes have the best view; from here they rise two hours before the Sun and reach 20° high in the ESE at Mars' disappearance. From latitudes 35° South and 45° South the pair rise a little over 2 hours before sunrise, reaching 19° and 18° above the Eastern horizon, respectively. Through the telescope, gibbous Venus appears 11".3 in apparent diameter - over 2½ times larger than Mars.
A morning conjunction between Mars and Uranus on July 15th 2024 takes place near Taurus' Western border with Aries (about 6° SSE of The Pleiades star cluster). With an angular separation between the two planets of about one apparent Full Moon diameter (0°.5) the pair can easily be contained within the field-of-view of a wide telescopic eyepiece. At magnitude +0.9, Mars shines about 86 times brighter than its distant companion. As Uranus disappears from view at first light the two planets are positioned 39° high in the ENE at the Equator, 31° high in the North-east at 25° South, 26° high in the North-east at 35° South and 19° high in the NNE at 45° South. Southern hemisphere observers can view the event for a period between 2¼ hours (from 45° South) and 2¾ hours (from the Equator). In the lower Northern hemisphere, the pair are positioned towards the East as dawn commences, the altitudes being as follows: 20° high at 40° North, 29° high at 30° North and 34° high from the Northern Tropics. The planets are visible for between 2 hours (from 40° North) and 2½ hours (from the Northern Tropics). At the moment of conjunction Uranus is twelve times further away than Mars and through telescopes it appears about two-thirds of the apparent disk size of the Red Planet.
The closest conjunction of the apparition is that between Mars and Neptune on the morning of April 29th 2024, though owing to the dimness of the latter planet it requires optical aid to be viewed. The event is only observable South of about latitude 31° North. At best, Southern Tropical latitudes see the pair at 22° above the Eastern horizon when Neptune disappears from view at first light, being visible for about 1½ hours after rising. At Northern Tropical latitudes the pair are only 10° high in the East whilst at mid-Southern latitudes they are around 20° high in the ENE. Telescopically Mars appears almost twice as large as Neptune and shines 525 times brighter! Given the separation of only 2'.3 (0°.04) the Red Planet must be positioned outside of the telescopic field of view in order to comfortably glimpse the distant pale blue planet.
There are three conjunctions of Mars with Mercury during the period; one in the morning sky (near the start of the apparition) and two in the evening sky (near the end of the apparition). The narrowest separation between the two is in the morning sky on January 27th 2024, when Mercury passes just 14'.5 (0°.24) to the North of Mars in Sagittarius. Adding to the event is brilliant white Venus, some 12° away to the West, now more than half-way through its 2023-24 morning apparition. The best view of the conjunction is had from Equatorial and Southern Tropical latitudes, from where the pair reach about 15° above the ESE horizon when the fainter planet (Mars) disappears from view in the dawn twilight. From the mid-Southern hemisphere they reach 13° high (35° South) and 11° high (45° South), both in the ESE. From low-Northern latitudes the pair are seen in continuous twilight, attaining just 8° high in the ESE as the Red Planet fades from view. The conjunction is observable for around 50 minutes (from 25° to 35° South), 40 minutes (from the Equator and 45° South) and just 15 minutes (from 30° North).
The evening conjunction between Mars and Mercury on October 21st 2025 shares similarities with that of January 2024, although of course it takes place in the Western sky and not the Eastern: the planets are positioned in the far South of the zodiac, around 21° from the Sun and are of similar magnitudes. It is, however, the widest of the eight conjunctions in 2024-25, the pair being a sizeable 2°.0 apart. The viewing circumstances are also similar to those of January 2024: Southern Tropical latitudes see the pair at about 15° above the WSW horizon when Mars appears into view in the dusk twilight, whilst at mid-Southern latitudes they are also in the WSW, at 14° high (35° South) and 13° high (45° South). Meanwhile at low-Northern latitudes the pair are just 4° above the WSW horizon as Mars comes into view at dusk. The event is observable for about an hour at Southern latitudes but just 15 minutes from low-Northern latitudes.
The most difficult conjunction to view in the 2024-25 period is that between Mars and Mercury in the dusk sky on November 12th 2025; indeed, it is only observable between about latitudes 6° North and 37° South. At best, they are 6°-7° high in the WSW when first seen in the Southern Tropics. South of about latitude 20° South the pair are seen in continuous twilight through to setting. The event is observable for no more than 15 minutes in each case.
The following table lists the observable conjunctions involving Mars during the 2024-25 apparition which take place at solar elongations of 15º or greater. Where other planets are also in the vicinity, details are given. Note that, because some of the conjunctions occur in twilight, the planets involved may not appear as bright as their listed magnitude suggests.
Mars conjunctions with other planets from January 2024 to November 2025 (click on the thumbnail for a full-size table). The column headed 'UT' is the Universal Time (equivalent to GMT) of the conjunction (in hrs : mins). The separation (column 'Sep') is the angular distance between the two planets, measured relative to Mars, e.g. on 2024 Feb 22, Venus is positioned 0°.6 North of Mars at the time shown. The 'Favourable Hemisphere' column shows the Hemisphere in which the conjunction is best observed. Note that observers located close to the Northern/Southern visibility boundary of any given conjunction will find it difficult or impossible to observe because of low altitude and/or bright twilight.
In the 'When Visible' column, a distinction is made between Dawn/Morning visibility and Dusk/Evening visibility; the terms Dawn/Dusk refer specifically to the twilight period before sunrise/after sunset, whilst the terms Evening/Morning refer to the period after darkness falls/before twilight begins (some conjunctions take place in darkness, others do not, depending upon latitude). The 'Con' column shows the constellation in which the planets are positioned at the time of the conjunction.
To find the direction in which the conjunctions are seen on any of the dates in the table, note down the constellation in which the planets are located ('Con' column) on the required date and find the constellation's rising direction (for Dawn/Morning conjunctions) or setting direction (for Dusk/Evening conjunctions) for your particular latitude in the Rise-Set direction table.
A table of planetary conjunctions involving Mars from 2021 to 2025 can be seen here.
Although any given conjunction takes place at a particular instant in time, it is worth pointing out that, because of the planets' relatively slow daily motions, such events are interesting to observe for several days both before and after the actual conjunction date.
There are in fact two methods of defining a planetary conjunction date: one is measured in Right Ascension (i.e. perpendicular to the celestial equator) and the other is measured along the ecliptic, which is inclined at 23½° to the Earth's equatorial plane (this is due to the tilt of the Earth's axis in space). An animation showing how conjunction dates are determined by each method can be found on the Jupiter-Uranus 2010-11 triple conjunction page. Although conjunctions measured along the ecliptic can be significantly closer, the Right Ascension method is the more commonly used, and it is the one which is adopted here.
Taurus, Gemini, Cancer & Leo:
Constellation Photographs
Photographs showing the region of the night sky through which Mars passes from July 2024 to July 2025 (click on the thumbnails for their full-size equivalents). From left to right, the photos are: Leo (red border), Cancer & Northern Hydra (yellow border), Gemini, Orion, et al (blue border) and Taurus (green border). In the bottom image, dashed lines indicate that the photo extends beyond the star chart's border.
The faintest stars visible in each photo are approximately as follows: Leo photo: mag. +8.0; Cancer photo: mag. +8.2; Gemini photo: mag. +6.5; Taurus photo: magnitude +8.0. Note that the photographs do not have the same scale because of the varying camera lens settings and image resolutions.
Moon near Mars Dates,
January 2024 to October 2025
The Moon is easy to find, and on one or two days in each month, it passes Mars in the sky. The following tables list the dates on which the Moon passes near the planet during its 2024-25 apparition:
The Moon moves relatively quickly against the background stars in an Eastward direction, at about its own angular width (0º.5) each hour (about 12º.2 per day). Because it is relatively close to the Earth, an effect called parallax causes it to appear in a slightly different position (against the background stars) when seen from any two locations on the globe at any given instant; the further apart the locations, the greater the Moon's apparent displacement against the background stars. Therefore, for any given date and time listed in the table, the Moon will appear closer to Mars when seen from some locations than others. For this reason, the dates shown in the table should be used only for general guidance.
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Mars Meridian Transit Altitudes,
2012 to 2031
Mars is one of only two Solar System planets whose surface details can be seen through modest-sized telescopes (the other being Mercury, whose small size and low altitude often precludes a clear view). For the naked-eye observer, apart from the increased likelihood of obstruction from trees and buildings, a planet's low altitude is generally of little consequence. However for the telescopic observer, high altitude is essential in order to minimise the effects of turbulence, atmospheric dimming and light pollution (skyglow) which prevails near the horizon. Consequently, telescopic observers consider high altitude transits (when a celestial body crosses the observer's meridian, reaching its highest point in the sky) as more favourable than low altitude transits. As a general rule, telescopic observation is best done when a celestial body's altitude is greater than about 30°; hence observation in the couple of hours after rising or before setting is best avoided, unless there is no other alternative.
Mars' meridian transit altitude (as seen from any given point on Earth) varies as the planet drifts Eastwards through the zodiac from one opposition to the next. The altitude at which an observer sees a planet at meridian transit is determined not only by the constellation in which the planet is positioned at the time, but also by the observer's latitude. As a result, certain apparitions are more favourable to observers in one hemisphere than to observers in the opposite hemisphere.
In general, high-Northerly oppositions (in Taurus or Gemini) are best seen from the Northern hemisphere and high-Southerly oppositions (in Scorpius, Ophiuchus, Sagittarius or Capricornus) are best seen from the Southern hemisphere. Prior to January 2025, Mars' last most Northerly opposition took place in Gemini in December 2007, when its declination () was +26°.8 (about 1°.7 further North than at the 2025 opposition); at such times observers at mid-Northern latitudes see the planet transit at around 60° to 70° high in the sky, providing optimal conditions for viewing through telescopes. Mid-Southern hemisphere observers fare rather worse under such circumstances, the planet transiting at only 20° to 30° high. After its 2007 opposition Mars began to descend the ecliptic, a process which continued through its next few oppositions in Leo (2012), Virgo (2014) and Scorpius (2016). After 2018 observing circumstances for Northern hemisphere observers gradually improved as the planet ascended the zodiac once more, reaching opposition in Pisces (2020), Taurus (2022) and Gemini (2025). Beyond 2025 the situation for Northern latitudes will worsen again, with oppositions taking place in Leo (2027), Virgo (2029), Libra (2031) and Sagittarius (2033).
Mars' last most Southerly opposition took place in Capricornus in July 2018, when observers at mid-Southern latitudes saw the planet transit at around 70° to 80° high in the sky; mid-Northern hemisphere observers saw it transit at just 20° to 30° high. Southern hemisphere observers, having experienced a few well-placed oppositions in 2014, 2016 and 2018, have seen observing circumstances worsen since that time, the lowest altitudes being reached at the 2022 and 2025 oppositions. Beyond 2025, however, observing circumstances for Southern hemisphere observers will improve over the next four oppositions. Mars' next most Southerly opposition will take place in June 2033, when it will be at its furthest point South of the zodiac ( = -27°.8) in Sagittarius.
The Red Planet's next closest and brightest opposition will be in Aquarius in September 2035, when it will be only 0.3815 AU (57 million kms or 35.4 million miles) from Earth and shine brightly at magnitude -2.8.
Meridian Transit altitudes of Mars at successive oppositions from 2012 to 2031, as seen from a variety of latitudes (click on the thumbnail for the full-size table). The planet's best (brightest) oppositions take place when it is positioned in Aquarius, as it was in 2003. During these times Southern hemisphere observers benefit from a high transit altitude, much like the situation in 2018 (when the planet was in neighbouring Capricornus). Conversely, at these optimal times observers at high and mid-Northern latitudes must contend with less-than-ideal transit altitudes (< 35°). Meanwhile, the Martian disk as seen through the telescope began to shrink after the 2018 opposition and will only begin to increase from the 2029 opposition. Meridian transit altitudes for the period 2001 to 2010 can be seen here.
The varying transit altitude of Mars at each opposition is not the only factor which affects the ability to see the planet's surface details through telescopes; there is also the question of its hugely varying apparent size as seen from the Earth. This is the result of the planet's eccentric orbit, which brings it closer to the Earth at some oppositions than at others. For more details, see the Mars oppositions 2012-2027 page.
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Copyright Martin J Powell November 2023
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