Elara

Elara, also known as Jupiter VII, is an irregular-shaped prograde satellite belonging to the outer planet, Jupiter. It was discovered by Charles Dillon Perrine at the Lick Observatory on January 2, 1905. Elara belongs to a group called the Himalia group, which is strangely located more than one hundred million miles from the planet Jupiter itself.

Formation
It is believed by astronomers that Elara was brought in by Jupiter's gravitational pull. Since it is asteroid-like in appearance, it is believed to come from the neighboring Asteroid belt.

Surface
The surface of Elara is mostly made of rock and different rocky substances. The surface is cratered and mostly covered in mountainous areas and plains. Many visible valleys and low areas are also seen on the surface, possibly due to previous impacts by other, smaller celestial objects.

Composition
Common between satellites of Jupiter, Elara is home to a porous ocean sandwiched between two layers about 300 km below the surface of Elara.

Exploration
Through the months of February and March of 2007, New Horizons took LORRI images of Elara from five million miles away on its expedition to the dwarf planet, Pluto.