Four and a half billion years ago, our Solar System was formed out of a huge cloud of dust and gas.
Top 10 Largest Bodies in The Solar System
|Body||Max Diameter (KM)||Max Diameter (Miles)||Size Compared with Earth|
Most of the planets have been observed since ancient times. The exceptions are Uranus, discovered on 13 March 1781 by the British astronomer Sir William Hershel; Neptune, founded by German astronomer Johann Galle on 23 September 1846; and, outside the Top 10, the former planet Pluto.
Top 10 Longest Years in The Solar System
|Body||Length of Year ( Years)||Length of Year ( Days)|
Top 10 Longest Days in The Solar System
|Body||Days (LOD)||HRS (LOD)||Mins (LOD)||Secs (LOD)|
Top 10 Largest Planetary Moons
1. Ganymede / Jupiter
Discovered by Galileo on 11 January 1610. Ganymede is thought to have a surface of ice of about 97 km (60 miles) think. Launched in 1989, NASA’s Galileo probe reached Ganymede in June 1996.
2.Titan / Saturn
Titan is larger than Mercury and pluto. We have no idea what its surface looks like because it has such a dense atmosphere, but radio telescope observations suggest that it may have ethane ‘oceans’ and ‘continents’ of ice or other solid matter.
3. Callisto / Jupiter
Possessing a similar composition to Ganymede, Callisto is heavily pitted with craters, perhaps more so than any other body in the Solar System.
4. Io / Jupiter
Io has a crust of solid sulphur with massive volcanic eruptions in progress, hurling sulphurous materials 300 km (186 miles) into space.
5. Moon / Earth
Our own satellite is a quarter of the size of Earth, the 5th largest in the Solar System and, to date, the only one to have been explored by humans.
6. Europa / Jupiter
Although Europa’s ice-covered surface is apparently smooth and crater-free, it is covered with mysterious black lines, some of them 64 km (40 miles) wide and resembling canals.
7. Triton / Neptune
Triton is getting progressively closer to Neptune, and it is believed that in several million years the force of the planet’s gravity may full it apart, scattering it into a form like the rings of Saturn.
8. Titania / Uranus
The Largest of Uranus’s 27 Moons. Titania was discovered by William Herschel on 11 January 1787. It has a snowball-like surface of the ice. Its size estimate was revised by data from Voyager 2.
9. Rhea / Saturn
Saturn’s 2nd largest moon was discovered on 23 December 1672 by Jean-Dominique Cassini. Voyager 1 confirmed that its icy surface is pitted with craters, one of them 225 km (140 miles) in diameter.
10. Oberon / Uranus
Oberon was discovered by Herschel at the same time as Titania, and given the name of the fairy king husband of Queen Titania. Data from Voyager 2 relegated Oberon from 9th to 10th place in this list.