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Titan

Saturn's largest moon and the second-largest in the Solar System. Titan is unique for its dense nitrogen-rich atmosphere and the presence of liquid hydrocarbon lakes and rivers on its surface.

Source: science.nasa.gov

APODs including "Titan"

Two Planet Opposition

08/10/2010

Two Planet Opposition
Image Credit: Peter Knappert / NASA APOD

In late September, two planets were opposite the Sun in Earth's sky, Jupiter and Uranus. Consequently closest to Earth, at a distance of only 33 light-minutes and 2.65 light-hours respectively, both were good targets for telescopic observers. Recorded on September 27, this well-planned composite of consecutive multiple exposures captured both gas giants in their remarkable celestial line-up accompanied by their brighter moons. The faint greenish disk of distant planet Uranus is near the upper left corner. Of the tilted planet's 5 larger moons, two can be spotted just above and left of the planet's disk. Both discovered by 18th century British astronomer Sir William Herschel and later named for characters in Shakespeare's A Midsummer Night's Dream, Oberon is farthest left, with Titania closer in. At the right side of the frame is ruling gas giant Jupiter, flanked along a line by all four of its Galilean satellites. Farthest from Jupiter is Callisto, with Europa and Io all left of the planet's disk, while Ganymede stands alone at the right.