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Finding Uranus: |
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Star map showing the path of Uranus against the background stars of Aquarius and Pisces from June 2006 to January 2019. Positions are marked for each opposition date and selectively for Eastern and Western stationary points. In this diagram, the marked stationary points are paired for each loop, e.g. the '2009 Jul' and '2009 Dec' stationary points occur in the same loop, the planet passing opposition in between, i.e. at '2009 Sep 17' (the planet will always be moving retrograde - East to West - when it passes opposition). Uranus describes a series of shallow, Southward-facing loops because the planet is South of the ecliptic (by less than 1º) throughout the period shown on the chart (the individual loops are not discernible in this chart because of the scale of the map; instead, each loop appears as a thickened line). Note that because of the distance of Uranus from the Earth, the angular width of each loop (about 3º.9 from Eastern to Western stationary points) is such that the loops have only a narrow gap between them. The star map applies to observers in the Northern hemisphere (i.e. North is up); for the Southern hemisphere view, click here. Printer-friendly versions of this chart are available for Northern and Southern hemisphere views (the above chart will help in finding the general location of the planet throughout the period in question, however a more detailed star chart will probably be required to pinpoint the planet precisely - for more details, see below). |
The Position of Uranus in the Night Sky, 2006 to 2019 by Martin J Powell
From June 2006 to March 2009, Uranus continued its motion through Aquarius, the Water Carrier, where it has been located since early 2002. From March 2009, Uranus began its passage through one of the zodiac's faintest constellations - Pisces, the Fishes.
Uranus reaches opposition to the Sun (when it is closest to the Earth and brightest in the sky for the year) every 369.6 days on average, i.e. about 4 days later in each successive year. The apparent magnitude of the planet varies little during the period shown in the star chart - from +5.7 (at opposition) to +5.9 (at superior conjunction).
The apparent diameter of the planet (its angular size when seen from the Earth) at opposition throughout the period covered by the star chart is 3".7 (3.7 arcseconds, where 1 arcsecond = 1/3600th of a degree).
Note that in 2010, Uranus reaches opposition on the same day as Jupiter (September 21st) with just five hours between their opposition times; Uranus will then be positioned 0º.8 to the North of the Giant Planet. A finder chart showing the two planets' paths during this period is provided below.
In February 2009 Uranus reached aphelion (its furthest point from the Sun; in this case 20.1 Astronomical Units or 3 thousand million kms) and consequently was at its most poorly-placed orbital position for observation from the Earth. The situation only slowly improves and Earthbound observers will have to wait until 2050 (when the planet is in Leo) before it reaches perihelion (its closest point to the Sun, at 18.28 AU or 2.73 thousand million kms) to see the planet at its brightest and best. Despite the closeness, however, the planet's opposition magnitude will only increase by about 0.4 magnitudes to +5.3.
Uranus will cross the celestial equator in Pisces in April 2011 (heading North-eastwards and moving direct), then in October 2011 (moving retrograde and temporarily heading South-westwards) and again in January 2012 (resuming North-easterly motion, moving direct). For the first time in over 41 years, the planet will then become visible for a longer period of time in the Northern hemisphere than in the Southern hemisphere (it last crossed the celestial equator - heading South-eastwards along the ecliptic - in Virgo in 1969).
Looking further ahead, the planet will continue its Northward motion along the ecliptic until it reaches its most Northerly point in Gemini in 2034, having crossed its ascending node on the ecliptic (crossing the ecliptic from South to North) in Taurus in 2029.
[Terms in yellow italics are explained in greater detail in an associated article describing planetary movements in the night sky.]
Twins Reunited
Further to the South-west (moving through Capricornus and, from 2010, through Aquarius) is Uranus' distant and elusive planetary 'twin' Neptune. From the viewpoint of the Earth, faster-moving Uranus 'overtook' Neptune when they were in Sagittarius in July 1993 (at which point they were in conjunction, i.e. at the same celestial longitude). This was the first time the two planets had been seen at conjunction since these planets were discovered (Uranus in 1781, Neptune in 1846). Conjunctions of these two planets are rare events indeed, occuring about every 172 years; the next one will take place in the year 2164.
Finding Uranus in Your Local Night Sky (General Location)
Where in the night sky should I look for Uranus tonight? In which direction and how high up will it be?
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, the local season 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).
Use the following Javascript program to help find Uranus in your night sky during 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 Uranus, refer to the 'Finding Uranus ..' 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 Uranus 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 of Uranus (its angular distance from the Sun as seen from the Earth) is less than about 20°, it 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 20°, making observation difficult or even impossible. This particularly applies throughout the local summer months at higher latitudes. To find the general location of Uranus in your Night Sky, 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 Uranus 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 explanatory diagrams below). If Uranus' altitude is less than about 10° it will probably 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
Uranus 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 Uranus rises in daylight (i.e. if the Sun is already above the horizon), you will have to wait until after dusk to see it - in which case, 'fast forward' to a time shortly after sunset, then note down the time and direction. This will provide you with the general location of the planet in your Night Sky at the time you have requested. A more detailed 'star hop' will be required to pinpoint the planet precisely - for details, see the section 'Finding Uranus from 2006 to 2018' below.
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Finding Uranus from Jupiter, May 2010 to February 2011
During the 2010-2011 period the bright planet Jupiter passes Uranus while in Pisces, describing its significantly larger planetary 'loop' about one apparent Full Moon-diameter to the South of Uranus. Since Jupiter is such an easy naked-eye object (use the Mini-AstroViewer® Java applet above to find it), the close approach of the two planets during this interval provides a good opportunity to find Uranus with relative ease; for this purpose, a finder chart is provided below.
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| Paths of Jupiter and Uranus, in South-western Pisces, marked on the first day of each month for the period from May 2010 to February 2011. Much of the star field in the chart should be easily contained within a binocular field of view (which typically ranges from 5° to 9°). Stars are shown down to magnitude +8.5. Right Ascension and Declination co-ordinates are marked around the border, for cross-referencing in a star atlas. A Southern hemisphere view can be found here. Printer-friendly (greyscale) versions of the chart are available for Northern and Southern hemisphere views. Move your pointer over the chart (or click here) to see a 'clean' star map of the area (without planet paths); observers may wish to use the 'clean' star map as an aid to plotting the two planets' positions on a specific night - in which case, a printable version can be found here. Three conjunctions between these planets (see below) take place during the period indicated on the chart, i.e. on June 6th 2010, September 22nd 2010 (opposition day) and January 2nd 2011. On these dates, a line drawn vertically through the two planets (i.e. in relation to Celestial North) show them to be in alignment. Having identified Uranus' location, the author recommends that Jupiter be positioned just outside the binocular field to minimise the likely effects of glare from that planet. Ideally, searches for Uranus should be carried out on Moonless nights, i.e. in the two-week period centred on the New Moon in any given month. The apparent magnitudes of selected stars in the region (down to magnitude +8.5) are shown in brackets in this chart. |
The Jupiter-Uranus Triple Conjunction, June 2010 to January 2011
As Jupiter and Uranus pass each other in the sky from 2010 to 2011, they undergo a series of three conjunctions (i.e. they reach the same celestial longitudes) over a seven-month period; this is referred to as a triple conjunction, and they are relatively rare events (the last one between Jupiter and Uranus took place in 1983). An animation demonstrating the principle of the triple conjunction - and showing how conjunction dates are defined - is provided in the information box below.
The first of the 2010-11 conjunctions takes place on June 6th 2010, when both Jupiter (at magnitude -2.3) and Uranus (at magnitude +5.9) are moving direct (or prograde, i.e. West to East) against the star background. The two planets are separated vertically by 29' (29 arcminutes, or just under half a degree) at this point, and are visible in the early morning sky. The second conjunction takes place on September 22nd 2010, when both Jupiter (mag. -2.9) and Uranus (mag. +5.7) are retrograding (moving East to West) against the star background; the planets are separated by 53' (0°.88) at this point, and are visible throughout the night. This is also the day on which both planets reach opposition to the Sun, there being just 5 hours separating the two planets' opposition times (this is known as a paired opposition). Finally, the planets are again in conjunction on January 2nd 2011, when both Jupiter (-2.3) and Uranus (+5.9) have resumed direct motion, the pair then being separated by 34' (0°.56); this conjunction is visible in the evening sky, shortly after sunset.
The next triple conjunction between these two planets will be in 2037-8, when they are both in Gemini. Conjunctions of any kind between these two planets (mostly single or double) occur, on average, about every 13.7 years. The next will be on April 20th 2024 (single, in Aries); this conjunction will be difficult to see because the two planets will be close to the Sun at the time. The next meeting of the two planets after this will be the aforementioned triple conjunction (September 8th 2037, February 19th 2038 and March 30th 2038). All three of these conjunctions will be easy to see.
How are Planetary Conjunction dates determined? There are two ways of determining 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). The conjunction dates determined by each method can differ by up to several days, depending upon the positions of the planets involved and their relative angular motions. Both of these methods are demonstrated in the diagrams below, which animate the Jupiter-Uranus triple conjunction of 2010-11. |
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Conjunction dates measured in Right
Ascension apply whenever two planets (or any two celestial bodies)
attain the same Right Ascension (RA). The RA is measured Eastwards along the
celestial equator from a point referred to as the First Point
of Aries,
marked by the Ram's head symbol ( The
RA is usually measured in hours, minutes and seconds; the varying
co-ordinates of the planets Jupiter ( When measured using the RA method, the angular separation of the two planets at the moment of conjunction is represented by the difference in declination between them (the declinations shown have been rounded to the nearest tenth of a degree). For example, at the September 22nd 2010 conjunction, the angular separation of the two planets is (2°.2 - 1°.3) = 0°.9, or about 54 arcminutes. |
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Conjunction dates measured
along the Ecliptic apply whenever two celestial bodies attain the same ecliptic
longitude (measured in degrees Eastwards along
the ecliptic from the First
Point of Aries). The
star map is overlaid with a grid marking 1° intervals in ecliptic
longitude (symbol The
ecliptic is defined as the apparent path of the Sun against
the background stars as viewed from
the Earth during the course of the year; therefore, the Sun's
apparent path always has an ecliptic latitude of 0°. The ecliptic
latitude of the planets, however, varies throughout their orbit;
during the period of time shown in the above diagram, both Jupiter
and Uranus are positioned to the South of the ecliptic
(indicated by a negative value of When measured using the ecliptic method, the angular separation of the two planets at the moment of conjunction is represented by the difference in ecliptic latitude between them. Hence, at the September 19th 2010 conjunction, the angular separation of the two planets is (1°.6 - 0°.8) = 0°.8, which is fractionally closer than the separation measured using the RA method. |
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Note that, at the June 2010 conjunction, the date using the ecliptic longitude method is two days later than that measured using the RA method. At the September 2010 conjunction it is three days earlier than that of the RA method and at the January 2011 conjunction it is again two days later. The conjunction dates determined by each method differ by their greatest extent when the relevant planets are positioned in the vicinity of Pisces and Virgo, i.e. the constellations in which the ecliptic intersects with the celestial equator (the situation for Pisces being illustrated above). Although conjunction dates determined using the ecliptic longitude method 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 the author has adopted here when quoting conjunction dates in the main text. |
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The Current Night Sky over Johannesburg,
South Africa
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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. |
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Finding Uranus from 2006 to 2018
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Uranus, photographed in moderately light-polluted conditions in August 2005, when the planet was in central Aquarius. When mounted on a tripod, modern-day digital cameras fitted with a zoom lens will easily detect the planet at shutter speeds of only a couple of seconds at higher ISO (film speed) settings. Some photos will even show the characteristic pale green colouration of the planet. The field of view is approximately 2º.8 by 3º.0 (move your pointer over the image to see the star magnitudes, or click here). |
From
late 2006 through 2007, pale-green
Uranus
was located to the
South-east of the asterism
(star pattern) unofficially known as
'The Steering
Wheel', in
the Northernmost region of Aquarius. Together
with its nearby star Sadalmelik (
Aqr or Alpha Aquarii, apparent
magnitude +2.9),
'The Steering
Wheel' is the most recognisable
feature of Aquarius
(the complete constellation can be seen on the Neptune
2006-2023
page).
The
'Steering
Wheel' is found
by looking West of the Circlet
of Pisces -
five stars in a roughly circular formation, which form the head of the Fishes
(there are actually seven stars in the circle; two fainter stars are not shown
on the map).
The Circlet
is itself found by looking
South of the Great
Square of Pegasus
- four fairly
bright stars forming a near-perfect square. The four stars are (moving clockwise
from North-east): Alpheratz
(
And or Alpha Andromedae, mag. +2.0), Scheat (
Peg or Beta Pegasi, mag. +2.4v), Markab (
Peg or Alpha Pegasi, mag.
+2.5) and Algenib
(
Peg or Gamma Pegasi, magnitude +2.8v).
Once
at the 'The Steering
Wheel', a
'star-hop'
will be required towards the South-east to the star 
Aqr
(Lambda Aquarii or 73 Aqr, mag. +3.7) which is shown in the star
map at the top of the page, next to the '2006 Nov' position of Uranus.
This star, together with 
Aqr (Phi Aquarii
or 90 Aqr, mag. +4.2) should be the main reference points of
all searches for the planet through to around early 2009. A finder chart
will most likely be needed to locate the planet with certainty (of which, see
below).
From early 2009, Uranus may prove a more tricky object to find because by then, the planet has moved into Pisces, a relatively faint constellation with no stars brighter than magnitude +3.6. This having been said, the track which the planet takes through the constellation is along a region of faint stars, so at any given time, Uranus will be one of the brightest objects - if not the brightest object - seen in the area immediately around its track (i.e. within a typical binocular field of vision).
From around April 2008 to early 2010, the planet can be found to the South of the Circlet; from mid-2010, a star-hop will be required to find the planet, moving Eastwards from the Circlet. Again, a finder chart will be needed to locate the planet with certainty.
The bright planet Jupiter passes to the South of Uranus from 2010-11; during this interval, only a short 'star hop' from Jupiter will be required to find it (see finder chart above).
Around all opposition dates shown on the map, the planet will be due South at local midnight in the Northern hemisphere (due North at local midnight in the Southern hemisphere).
|
The New Solar System: Ice Worlds, Moons and Planets Redefined Patricia Daniels & Robert Burnham |
Uranus, Neptune and Pluto and How to Observe Them (Astronomers' Observing Guides) Richard Schmude, Jr |
Atlas of Uranus Garry E. Hunt & Sir Patrick Moore |
Uranus: The Planet, Rings and Satellites Ellis D. Miner |
Why Is Uranus Upside Down? And Other Questions about the Universe Fred Watson |
The Georgian Star: How William and Caroline Herschel Revolutioned Our Understanding of the Cosmos Michael D. Lemonick |
Dark Side Of The Moon Wernher Von Braun, The Third Reich and The Space Race Wayne Biddle |
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Finding Finder Charts for Uranus on the Web
Finder charts for locating Uranus - showing a smaller area of sky and fainter stars - are published on a variety of websites, such as Paul Money's AstroSpace site and the Royal Astronomical Society of New Zealand (in this case the available star chart shows the Southern hemisphere view, with South up and East to the right; they will need to be inverted for the Northern hemisphere view). Northern hemisphere charts for the current year can usually be found at the Sky & Telescope website by performing a search there on finding Uranus and clicking on the appropriate result. Charts at other websites can be found by using the following search engines (be sure to check the correct orientation of any chart found; it will need to be orientated North-up for Northern hemisphere observers and South-up for Southern hemisphere observers):-
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Northern Hemisphere |
Southern Hemisphere |
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YAHOO! |
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Windows Live |
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Positions of the Superior Planets:
|
Mars, 2009-2010 |
Jupiter, 2009-2011 |
Saturn, 2006-2013 |
Neptune, 2006-2023 |
Pluto, 2006-2022 |
Current Position of the Sun and the Brighter Naked-Eye Planets (Star Map)
Credits
Copyright © Martin J. Powell December 2006; updated November 2008, April 2009, June 2009
) 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 (
)
in
the above diagram. The First Point of Aries is the
point at which the Sun crosses the celestial equator, heading Northwards,
at the Vernal Equinox (Spring equinox) on March 21st/22nd
of each year.
)
and Uranus (
)
are shown in the inset box. The star map is overlaid with a grid
marking 1° intervals in RA (equivalent to four minutes of time)
and Declination (degrees North or South of the celestial
equator).
