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The path of Saturn against the background stars of Leo, Virgo and Libra from September 2006 to December 2013, with positions marked on the first day of each month (click on the thumbnail for the full-size image). The dates are colour-coded by year; a quick-glance legend is in the lower right corner (e.g. all 2009 positions are shown in yellow). Periods when the planet was unobservable (i.e. when it was too close to the Sun, or passed behind it) are indicated by a dashed line; hence Saturn became lost from view (in the evening sky) in mid-August 2008 and became visible again (in the morning sky) in late September 2008. The chart shows the changing shape of Saturn's apparent looping formation as it moves through the zodiac. Saturn crossed the plane of the ecliptic (heading Northwards) in 2004-5, when it described a zig-zag formation in Gemini; it described hybrid formations (half loop, half zig-zag) during its passage through Cancer and into Leo, where they became conventional, Northward-facing loops. 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 on the map have an apparent magnitude of about +4.8. 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. A photograph of the region around Virgo, can be seen below; descriptions of the bright stars and deep-sky objects in the region (multiple stars, galaxies, etc.) can be found here. |
The Position of Saturn in the Night Sky:
2006 to 2013
by Martin J. Powell
Having spent the period from mid-2005 to mid-2006 in the constellation of Cancer, the Crab, Saturn entered Leo, the Lion, in August 2006. Its next three looping formations took place in this constellation, spending three years there before crossing into Virgo, the Virgin, in September 2009. Saturn crossed the celestial equator (declination = 0°), heading Southwards, in late September 2010. It was positioned in Virgo for a little over three years before it entered Libra, the Scales (or the Balance) in early December 2012. Six months later, in mid-May 2013, the ringed planet returned to Virgo, moving retrograde and reaching its western stationary point in July, before re-entering Libra in late August 2013.
Details of the seven Saturnian oppositions covered by the above star map, together with the dates on which the planet reached superior conjunction (when it passed behind the Sun as seen from the Earth) are given in the table below. Note how the planet's appearance changed markedly at each opposition, the ring system displaying varying tilt angles to the Earth as it orbited the Sun (for more details, see the diagram of Saturn's orbit).
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Apparition Period |
Opposition Circumstances |
Superior Conjunction |
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Opposition Date |
Constellation |
Declination |
Apparent Magnitude |
Diameter (arcsecs) |
Ring Tilt |
View from Earth (North up) |
Distance (AU)* |
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Globe |
Ring |
from Earth |
from Sun |
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2006/7 |
2007 Feb 10 |
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Leo |
+15°.6 |
0.0 |
20".3 |
46".0 |
-13°.9 |
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8.2003 |
9.1869 |
2007 Aug 21 |
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2007/8 |
2008 Feb 24 |
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Leo |
+11°.3 |
+0.2 |
20".0 |
45".3 |
-8°.3 |
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8.2914 |
9.2804 |
2008 Sep 4 |
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2008/9 |
2009 Mar 8 |
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Leo |
+6°.7 |
+0.5 |
19".8 |
44".9 |
-2°.6 |
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8.3944 |
9.3865 |
2009 Sep 17 |
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2009/10 |
2010 Mar 22 |
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Virgo |
+1°.8 |
+0.5 |
19".5 |
44".2 |
+3°.1 |
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8.5038 |
9.4992 |
2010 Oct 1 |
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2010/11 |
2011 Apr 3 |
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Virgo |
-2°.9 |
+0.3 |
19".3 |
43".7 |
+8°.6 |
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8.6139 |
9.6128 |
2011 Oct 13 |
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2011/12 |
2012 Apr 15 |
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Virgo |
-7°.5 |
+0.2 |
19".1 |
43".3 |
+13°.7 |
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8.7196 |
9.7220 |
2012 Oct 25 |
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2012/13 |
2013 Apr 28 |
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Libra |
-11°.7 |
+0.1 |
18".9 |
42".8 |
+18°.1 |
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8.8162 |
9.8220 |
2013 Nov 6 |
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* 1 AU (Astronomical Unit) = 149,597,870 kms (92,955,807 statute miles) |
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Saturn opposition data for the period 2007 to 2013. The Declination is the angle of the planet to the North (+) or South (-) of the celestial equator; on the star chart, it represents the planet's angular distance above or below the blue line. The angular diameter (or apparent size) of the planet as seen from Earth is given in arcseconds (where 1 arcsecond = 1/3600th of a degree). Note that Saturn's distance slowly increased over the period (as its headed towards aphelion), causing its angular diameter to shrink slightly year by year. The planet's apparent magnitude (brightness), after reaching a low point as the Earth passed through the ring-plane in 2009, began to brighten once more, despite the planet's increasing distance from the Earth. This is because the rings began opening up to view after 2009, reflecting more light back towards the Earth. The Ring Tilt (the ring plane opening angle to the Earth) is positive (+) when Saturn's Northern hemisphere was tipped towards the Earth and negative (-) when the planet's Southern hemisphere was tipped towards the Earth; the maximum value it can attain is ±27°.0. The Ring Tilt values were obtained from the SETI Institute's Saturn Ephemeris Generator 2.3. All other data was obtained from 'MegaStar', 'Redshift', 'SkyGazer Ephemeris' and 'AstroViewer' software and the Saturn images were modified by the writer from NASA's Solar System Simulator. |
[Terms in yellow italics are explained in greater detail in an associated article describing planetary movements in the night sky.]
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Saturn Conjunctions with other Planets, 2012 to 2013
The following table lists the conjunctions involving Saturn which took place between 2012 and 2013 at solar elongations of greater than 15°. In several cases, other planets were also in the vicinity and these are detailed. Note that, because some of the conjunctions occurred in twilight, the planets involved may not have appeared as bright as their listed magnitude suggests.
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Saturn conjunctions with other planets from 2012 to 2013 (there were no visible conjunctions involving Saturn in 2011). 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 Saturn, e.g. on 2012 Nov 27, Venus was positioned 0°.5 South of Saturn at the time shown. The 'Favourable Hemisphere' column shows the Hemisphere in which the conjunction was best observed. The expression 'Not high N Lats' indicates that observers at latitudes further North than about 50°N were likely to have found the conjunction 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 were positioned at the time of the conjunction. To find the direction in which the conjunctions were seen on any of the dates in the table, note down the constellation in which the planets were 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. |
Bright Stars, Nearby Stars and Galaxies
Descriptions of the bright stars and other interesting objects shown on the star chart can be found on the Zodiacal Sky: Cancer-Leo-Virgo page.
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Moon near Saturn Dates, 2013
On one or two days in each month, the Moon can be used as our celestial guide to help in locating Saturn in the sky. Use the following table to determine on which dates the Moon was in the vicinity of the planet:
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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 have appeared closer to Saturn when seen from some locations than from others. For this reason, the dates shown in the table should be used only for general guidance.
Credits
.Copyright Martin J Powell April 2009
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