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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. The positions 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 of invisibility (i.e. when the planet is too close to the Sun, or passes behind it) are indicated by a dashed line; hence the planet 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 a planet'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 (to find Leo and Virgo from The Big Dipper, see the animation below). Saturn crossed the celestial equator (declination = 0°), heading Southwards, in late September 2010. It will be positioned in Virgo for a little over three years before it enters Libra, the Scales (or the Balance) in early December 2012. Six months later, in mid-May 2013, the ringed planet returns to Virgo, moving retrograde and reaching its western stationary point in July, before re-entering Libra in late August 2013.
Saturn reaches opposition to the Sun (when it is closest to the Earth and brightest in the sky for the year) every 378 days, i.e. about 13 days later in each successive year. Details of the seven Saturnian oppositions covered by the above star map are given in the table below. Around opposition, Saturn is due South at local midnight in the Northern hemisphere (due North at local midnight in the Southern hemisphere). Note how the planet's appearance changes markedly at each opposition, the ring system displaying varying tilt angles to the Earth as it orbits the Sun (for more details, see the diagram of Saturn's orbit). Like the other Solar System planets, Saturn's apparent size (its angular diameter as seen from the Earth) varies slightly at each opposition because its orbit is slightly elliptical.
The dates on which Saturn reaches superior conjunction (i.e. when it passes behind the Sun as seen from the Earth) are also shown in the table. The planet is not normally visible from the Earth for about two weeks on either side of these dates.
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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 increases over the period (as its heads 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 passes through the ring-plane in 2009, begins to brighten once more, despite the planet's increasing distance from the Earth. This is because the rings begin 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 is tipped towards the Earth and negative (-) when the planet's Southern hemisphere is 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 author from NASA's Solar System Simulator v4.0. |
The rings will be fully on display again in 2017, when the planet is on the Ophiuchus/Sagittarius border and ideally placed for Southern hemisphere observers. Although it will then be near its greatest possible distance from the Earth, and at its lowest possible viewing altitude for Northern hemisphere observers, Saturn's presentation of its Northern hemisphere and ring face will nonetheless be an impressive sight. The planet will reach aphelion (its furthest orbital point from the Sun) in Sagittarius in April 2018, when it will be 10.065 Astronomical Units from the Sun (where 1 AU = 149,597,870 km or 92,955,807 statute miles). Saturn will reach its most Southerly position in the zodiac just six months later, in October 2018.
By a stroke of good luck on nature's part, Saturn's perihelion (its closest orbital point to the Sun) takes place only a short while after the planet's Southern pole is tilted at its greatest angle towards the Earth, so at these times - namely, every 29½ years - we are treated to a splendid, 'close-up' view of both the globe and the ring system when seen through Earthbound telescopes. For Northern hemisphere observers the situation is even better: whenever it is near perihelion, Saturn rides high in the sky on the Taurus/Gemini border, giving the best possible observing conditions. Saturn last passed perihelion in July 2003 and will next pass it in December 2032 (when it will be in Gemini); it will then be 9.015 AU (838 million miles or 1,348 million kms) from the Sun. The planet will reach its most Northerly point in the zodiac some six months later, in April 2033.
[Terms in yellow italics are explained in greater detail in an associated article describing planetary movements in the night sky.]
Saturn Conjunctions with other Planets, 2012 to 2014
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 conjunction or an appulse. However, not all conjunctions will be visible from the Earth because many of them take place too close to the Sun. Furthermore, not all conjunctions 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.
The majority of conjunctions involving Saturn are not particularly spectacular to view because the planet is usually positioned far away from the Earth - and is therefore not particularly bright - whenever they occur. Those involving Venus will always take place at solar elongations of less than 47° from the Sun, whilst those involving Mercury will always take place at 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 (Saturn looking like an ordinary, pale-yellow star).
Saturn's most interesting conjunctions take place when the planet is within a few months of opposition - and is therefore very bright - at which times they involve either Jupiter or Mars; these events are however very rare. Most conjunctions between Saturn and Jupiter (or Saturn and Mars) occur at elongations of less than 90°, when Saturn is far from its brightest in any given apparition. During the period from 2012 to 2014, for example, all the visible conjunctions take place at elongations of less than 75°, Saturn being fainter than apparent magnitude +0.6 in all cases. When Saturn's rings are well-presented to the Earth, the planet's apparent magnitude brightens significantly. A conjunction between Saturn and Mars in Southern Ophiuchus on August 25th 2016 - when the rings are close to their maximum opening angle - will see Saturn shine at magnitude +0.5 and Mars at magnitude -0.4. With both planets positioned some 97° to the East of the Sun, this conjunction will be easily seen against a dark Western sky after sunset.
The following table lists the conjunctions involving Saturn which take place between 2012 and 2014 at solar elongations of greater than 15°. In several cases, other planets are also in the vicinity and these are detailed. Note that, because some of the conjunctions occur in twilight, the planets involved may not appear as bright as their listed magnitude suggests.
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Saturn conjunctions with other planets from 2012 to 2014 (there are no visible conjunctions involving Saturn in 2011 or 2015). 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 is positioned 0°.5 South of Saturn at the time shown. The 'Fav. Hem' column shows the Hemisphere in which the conjunction will be best observed (Northern, Southern and/or Equatorial). The expression 'Not high N Lats' indicates that observers at latitudes further North than about 50°N will find 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 are positioned at the time of the conjunction. To find the direction in which the conjunctions will be 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 apparitions) or setting direction (for Dusk/Evening apparitions) for your particular latitude in the Rise-Set direction table. |
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. along 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 conjunction dates measured along the ecliptic are technically more accurate (separations between planets can be significantly closer) the Right Ascension method is the more commonly used, and it is the one which is adopted here.
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Telescopes, Binoculars and Spotting Scopes for Astronomy |
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Celestron Astromaster 70 AZ Telescope Celestron |
Orion AstroView 90mm Equatorial Refractor Telescope Orion |
Celestron NexStar 8 SE Computerised Telescope Celestron |
Barska Blackhawk 20-60x60 Waterproof Spotting Scope Barska |
Leupold Cascades 10 x 42 Binoculars Leupold |
Nikon Action Ex Extreme 10 x 50 All Terrain Binoculars Nikon |
Celestron SkyMaster 25 x 70 Porro Prism Binoculars Celestron |
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Martin J Powell is a participant in the Amazon Europe S.à r.l. Associates Programme, an affiliate advertising programme designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.co.uk, Amazon.de and Amazon.fr |
Saturn Through the Telescope
Saturn is arguably the most beautiful of all the planets to view through a telescope; indeed, many say it is the most beautiful telescopic object in the entire night sky. It is certainly one of the first objects that beginner astronomers turn their telescopes upon.
Even small telescopes at 50x magnification will reveal the planet's impressive ring system - the finest of all the outer gas giants - although larger telescopes are required to see the ring's individual regions. The rings are not always on view, however; about every 14¾ years the Earth passes through the planet's ring plane, causing them to almost disappear from view (for more details, see the Saturn orbit diagram).
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A Telescopic View of Saturn obtained by pointing a video-camera through the eyepiece of an 8-inch reflecting telescope in January 2004, some two weeks after the planet's opposition at the end of 2003. The rippling effect simulates how the Earth's turbulent atmosphere affects the steadiness of the telescopic image. |
The rings are classed into three main regions: A (the outermost), B (the brightest) and C (innermost). Ring B is the most easily seen, the inner region being slightly darker than the outer region. Separating rings A and B is the Cassini Division, which can be seen in 75mm (3 in) telescopes when seeing conditions are good. Within ring A, the much fainter Encke's Division typically needs larger instruments to resolve. Ring C (also known as the Crêpe Ring) is faint and difficult to see, requiring large telescopes. Several other rings were discovered by the Pioneer, Voyager and Cassini spacecraft; these rings are, of course, too faint to be detected from the Earth.
Like Jupiter, the darker bands running across Saturn's globe are known as belts and the lighter bands are referred to as zones. Saturn's globe is relatively featureless, with only a couple of low-contrast cloud belts visible for much of the time; the absence of distinct features is partly due to a layer of haze in the planet's upper atmosphere obscuring the view of the weather patterns beneath. Observing the planet in twilight (hence reducing the glare against the background) - or using blue filters - can sometimes help to enhance the planet's cloud features.
White spots or white ovals occasionally appear on Saturn and whenever they do, they are usually short-lived phenomena, lasting from only a few days to a few months. A prominent white spot appeared in 1933 (discovered by British comic actor and amateur astronomer Will Hay) and another in late 2010 (discovered by Australian amateur Anthony Wesley) became the most widely-observed spot in Saturn's observational history.
There is some evidence to suggest that, for any particular region of the planet, Saturn's Great White Spots (GSWs) re-appear about every 57 years (just under two Saturnian years). GSWs were recorded in Saturn's Equatorial Zone (EZ) in 1876, 1933 and 1990. In the Northern Tropical Zone (NTropZ) GSWs were sighted in 1903 and 1960. The 2010 GSW also seems to have had a precursor - in the same region of the planet - in 1953. Thus we might expect to see a GSW appear in Saturn's Northern hemisphere in 2017, i.e. 57 years after the 1960 event.
Whenever white spots appear, many amateurs attempt to determine their rotation period around the planet. In order to do this, the time at which the spot crosses the planet's central meridian is noted on several occasions (for more details on how a planet's central meridian longitude is defined, see the section on 'Mars Through the Telescope'). The larger spots are usually observed over a prolonged period, during which time they typically spread out in longitude, eventually encircling the planet before fading out of view.
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The view of Saturn through the telescope (above right) reveals what a typical small-to-medium-sized telescope is likely to see under average observing conditions. The image was recorded through an astronomical telescope, so the image is inverted (South-up when viewed from the Northern hemisphere). Hence in this view from early 2004, we see the planet's Southern hemisphere tipped in our direction (i.e. the planet's South Pole is at the top). The rings are almost fully presented (the ring opening angle or tilt is about -26°) and since it is soon after opposition, the shadow of the globe on the rings is cast directly behind the planet (this is in contrast to the situation at eastern or western quadrature, when the shadow appears slightly to one side, e.g. see the section on the superior planets' movements in the night sky). A faint, slightly darker cloud belt (the Southern Equatorial Belt or SEB) can just be discerned crossing the globe. Ring A is clearly darker than B and they are easily separable, however the seeing conditions are too poor to discern the Cassini Division between them. The innermost region of Ring B appears darker as it approaches the Crêpe Ring (Ring C) which in this case is barely discernible.
Since the 1950s, an interesting effect called the opposition effect or the opposition surge has been identified among numerous Solar System bodies. In the case of Saturn, it is sometimes referred to as the Seeliger effect (after German astronomer Hugo von Seeliger, who first noted it in the nineteenth century). The Seeliger effect is a sudden brightening of the planet's rings in the hours around the moment of opposition, i.e. when the planet is directly opposite the Sun in the Earth's sky. Naturally, the effect is most marked when the planet's rings are wide open to view. The Seeliger effect is not normally accounted for in Solar System modelling (e.g. when calculating a planet's opposition magnitude) because it is somewhat ephemeral and is not always observed. It is believed to be caused by the "coherent backscatter of light from the icy particles in the ring system as the phase angle approaches zero".
Several moons of Saturn can be seen through telescopes, the brightest of them being Titan - for more details, see below.
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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Virgo and Corvus A photograph showing the region of the night sky which Saturn passes through during the 2009-12 observing seasons. The picture was taken from latitude 51½° North in the early morning hours of late January 2006. Virgo is seen at meridian transit (due South) and the distinctive keystone-shape of Corvus is below it in the South-South-west. Both Leo and Crater are in the South-west (only the tail-end of Leo is visible in the photo). Stars in the upper region of the photo are visible down to about magnitude +8.0. Near the horizon, distant clouds (illuminated by streetlights) block Hydra's Eastern half from view. (Move your pointer over the image to identify the constellations and click on the image for a full-size picture). |
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Finding Leo and Virgo from The Big Dipper The well-known asterism (star group) known as The Big Dipper (or The Plough) in Ursa Major (The Great Bear) can be used as a starting point to finding Leo and Virgo in the night sky (provided these constellations are above the observer's horizon at the required time). To
find Leo,
use 'The
Pointer Stars'
Dubhe
(pronounced 'DUB-ee', To
find Virgo,
use the 'handle stars' of The
Dipper (the
'handle' of The
Saucepan)
to
project an arc in a Southward direction until you come across the
bright, orange-coloured star Arcturus
( From
Arcturus,
continue
the arc Southwards to the bright star Spica
(pronounced 'SPY-kah', or Note that this method primarily applies to Northern hemisphere observers. Southern hemisphere observers can only use this method if they are situated North of latitude 28° South (The Big Dipper is not wholly visible at latitudes further South than this). Observers at mid-Southern latitudes should instead use the AstroViewer Java applet below. A diagram showing the lines pointing to Leo and Virgo from The Big Dipper can be seen here. |
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Moon near Saturn Dates, 2012
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 to see the Moon in the vicinity of the planet:
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Moon near Saturn dates for 2012 (no information is given for October because Saturn is too near the Sun at this time). The Date Range shows the range of dates worldwide (allowing for Time Zone differences across East and West hemispheres). Note that the dates, times and separations at conjunction (i.e. when the two bodies are at the same Right Ascension) are measured from the Earth's centre (geocentric) and not from the Earth's surface (times are given in Universal Time [UT], equivalent to GMT). The Sep. & Dir. column gives the angular distance (separation) and direction of the planet relative to the Moon, e.g. on July 25th at 19:08 UT, Saturn is 6°.0 North of the Moon's centre. The Moon Phase shows whether the Moon is waxing (between New Moon and Full Moon), waning (between Full Moon and New Moon), at crescent phase (less than half of the lunar disk illuminated) or gibbous phase (more than half but less than fully illuminated). |
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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, or about 12º.2 per day) and 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 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.
Position of Saturn's Five Brightest Moons
Saturn's five brightest moons (satellites) - namely Titan (magnitude +8.3 at opposition), Rhea (+9.7), Tethys (+10.2), Dione (+10.4) and Enceladus (+11.7) - can readily be seen through telescopes, but only Titan (Saturn's largest moon) is visible through binoculars. The moons are seen to change their position in relation to each other from one night to the next.
Because of Saturn's relatively high axial tilt (26º.7 to the plane of its orbit) the Saturnian moons are mostly seen to follow apparent elliptical paths around the planet when viewed from the Earth (this is in contrast to, say, Jupiter's shallow axial tilt (3º.1), which causes its moons to present a more-or-less linear motion when seen from the Earth - see Jupiter's moon positions). However, the motion of Saturn's moons does appear more-or-less linear whenever the Earth crosses through the ring-plane of the planet, as it did in 2009. For about a year on either side of the ring-plane crossing date, transits (when a moon or its shadow passes across the planet's disk), occultations (when a moon passes behind the planet's disk) and eclipses (when a moon enters the planet's shadow) can be observed through telescopes.
The following Flash program shows the current position of Saturn's five brightest moons (based on your computer's clock and Time Zone settings):
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The Positions of Saturn's five brightest satellites in relation to the planet (the graphic requires the Adobe Flash Player plug-in to display correctly). Binocular and terrestrial telescope users in the Northern hemisphere should use the default 'Erect Image' (North up, East to the left) setting; Southern hemisphere observers using this equipment will need to click on the 'Inverted' (North down, West to the left) button. Users of astronomical telescopes in the Northern hemisphere will need to use the 'Inverted' option to match the view in their telescope, whilst those in the Southern hemisphere should use the default ('Erect Image') setting. The 'Mirror Reversed' button applies to astronomical telescopes with a star diagonal attached. Enter the required values for Date (in the form mm/dd/yyyy) and Time and click on 'Recalculate' to see the position of the moons for any date and time between January 1st 1900 AD and December 31, 2100 AD. The Timezone offset from UT is determined by the settings in your web browser. Times of all events in the program are given in Universal Time (UT) which is equivalent to Greenwich Mean Time (GMT). The 'Saturn's Moons' program by John Bartucci is available as a standalone, executable (exe) file which can be downloaded from the The Wilderness Center Astronomy Club website. |
A Java applet showing all of the above moons with an additional three - namely Iapetus (which varies between magnitudes +10.2 and +11.9 at opposition), Mimas (+12.9 at opposition) and Hyperion (+14.2 at opposition) - can be found at the BAA's Computing Section website.
Finding Saturn in Your Local Night Sky
Where in the night sky should I look for Saturn tonight? In which direction and how high up will it be?
Through to 2013, when it is positioned in Leo or Virgo, Northern hemisphere observers can easily find Saturn using The Big Dipper (or The Plough) asterism as a starting point; for details, see the animation above.
The location of a planet (or any other celestial body) in your local night sky depends upon several factors: the constellation in which it is positioned, your geographical latitude and longitude and the date and time at which you observe. To find a planet in the night sky at any particular date and time, we must know two things: a direction in which to look along the observer's horizon (eg. Southeast, East-Southeast) and an angle to look above the horizon (known as altitude or elevation).
The following Javascript program can be used to help find Saturn (and any other planets) in your night sky throughout the year:
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For additional information on the fully-functional version of the program, see here. |
Mini-AstroViewer® is an easy-to-use Java applet which shows the positions of the celestial bodies in the night sky for any location on the globe at any time of the year (Javascript must be enabled in your browser for the program to function). To activate the program, click on the button below (the program will open in a pop-up window). The default location is New York, USA. To select your own location and then find Saturn, refer to the 'Finding Saturn ..' box below. An animated tutorial showing how to locate a planet in the night sky using Mini-AstroViewer® can be seen here.
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Finding Saturn in Your Own Night Sky using Mini-AstroViewer®
To set your own location, click on the 'Location' button and click on your approximate position on the pop-up world map. If you know your precise latitude and longitude, you can refine your position by pressing the left/right and up/down arrows to move the cross-hair in 1° increments (to find your latitude and longitude, visit the Heavens Above website, select your country and enter the name of your nearest town or city using the 'Town Search' facility). Having plotted your geographical co-ordinates, click 'OK' and the night sky over your own location will appear in the window, valid for the current time, which is displayed in UT (Universal Time, equivalent to GMT). The applet will initialise displaying the current UT time according to your browser's clock and Time Zone settings (if you would prefer to have the Local Time displayed, use the fully-functional version of the program at Astroviewer.com). The red circle represents the horizon around you; the lower half of the display represents the part of the sky you are facing. The centre of the circle is the point directly above your head (known as the zenith). The ecliptic (the path along which the Sun, Moon and planets will be found) is marked by a red dashed line, passing as it does through the zodiac constellations. The blue dashed line marks the apparent position of the celestial equator, which arcs across the sky from the due East point on the horizon to the due West point. The program plots stars down to magnitude +5.0. The bottom scroll bar rotates the horizon view, allowing for a view in any compass direction; the left-hand scroll bar zooms the sky in or out, and the right-hand scroll bar pans up (to the zenith) or down (to the horizon) whenever the view has been zoomed.
Infomation on a celestial body can be viewed by clicking on the object (in the case of a planet, its magnitude, distance, elongation and apparent diameter). Note that if the elongation (its angular distance from the Sun as seen from the Earth) is less than about 15°, the planet will not be visible because it is too near the Sun. Remember that local twilight can affect the visibility of a particular planet, even at elongations greater than 15°, making observation difficult or even impossible. This particularly applies throughout the local summer months at higher latitudes. To locate Saturn, first see if it is above the horizon at the time you are requesting. If it is visible within the circle, move the bottom scroll bar left or or right to rotate the image until the planet is positioned on the vertical red line (the altitude scale). Zoom in to the area using the left-hand scroll bar where necessary (see animation opposite). The direction of Saturn at the requested time will be indicated at the bottom (W, SW, etc). The altitude of the planet (its angle above the horizon) can be read off on the altitude scale (it is marked at 10° intervals). Hence if it is three notches up, its altitude is 30° at the displayed time (to understand how to determine a planet's altitude in the night sky, refer to the two diagrams below). If Saturn's altitude is less than about 10° it may be difficult to see because of the dimming effect of the Earth's atmosphere and, in town and city locations, the effects of light pollution or skyglow. If
Saturn is not shown within the circle, it is below the horizon
and you will have to wait until after it next rises before you can see
it (provided it is not too near the Sun). To find when it next rises,
click the 'hours forward' button ( If Saturn rises in daylight (i.e. if the Sun is already above the horizon), you will have to wait until dusk to see it - in which case, 'fast forward' to a time shortly after sunset, then note down the time and direction. The same method can also be used to find any of the visible constellations in your night sky.
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The Current Night Sky over Coimbatore,
Tamil Nadu, India Requested location |
Would you like to see your own town or city shown here?
Requested locations may appear on another planet page (see links below) depending upon the number of requests received by the author at any given time. A list of the night sky locations currently displayed on this website can be seen on the main Naked-eye planets page. The graphic shows the sky at the location indicated when this page was loaded in your browser; if several minutes have since passed, click the 'Refresh' button at the top of your browser (or press the F5 key) to see the current sky. The Night Sky location displayed here is periodically changed by the website author. Additional AstroViewer® Information Mini-AstroViewer® is a lightweight version of AstroViewer®, an interactive night sky map that helps you find your way in the night sky quickly and easily. Due to its intuitive interface, it is well suited to beginners in astronomy. The fully functional, free-to-use version can be accessed at the AstroViewer® website. It has additional features such as a Local Time display, a planet visibility chart for any selected location, a 3D Solar System map, the ability to store user-generated world locations, a 'Find Celestial Body' facility, printing and language options and greater flexibility in the night sky display (see details here). A fully-functional version for offline use can be obtained upon the purchase of a license key, following the download and installation of a test version. AstroViewer® is produced by Dirk Matussek. |
Star Charts showing Positions of the Planets:
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Venus, 2011-2012 |
Mars, 2011-2012 |
Jupiter, 2011-2014 |
Uranus, 2006-2018 |
Neptune, 2006-2023 |
Pluto, 2006-2022 |
Current Position of the Sun and the Brighter Naked-Eye Planets ('Live' Star Map)
Credits
.Copyright © Martin J. Powell, April 2009, June 2009, revised December 2009
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) repeatedly until the planet
appears over the eastern horizon, then note down the time and direction
this occurs. By clicking the 'minutes/hours forward' buttons (
