Satellites in the solar system?
Can you list the satellites of the solar system ?
Some notes about satellites:-
Satellite is a natural object that orbits a planet or asteroid. Satellites are also called moons. All the planets except Mercury and Venus have satellites. The four giant planets, Jupiter, Saturn, Uranus, and Neptune, have many moons. At least one asteroid, called Ida, has a satellite.
Satellites vary greatly in size. The smallest one known, Ida's moon Dactyl, is about 1 mile (1.6 kilometers) across. The largest, Jupiter's Ganymede, has a diameter of 3,273 miles (5,268 kilometers). Of the more than 60 known satellites, about half have diameters greater than 60 miles (100 kilometers). A few satellites are larger than Pluto, the smallest planet. Ganymede and Saturn's moon Titan are also bigger than Mercury.
A satellite's composition depends on its distance from the sun and its geologic history. The satellites closest to the sun consist of a broad class of rock called silicate. This is the same material that makes up most of Earth's crust. The remaining moons are made up of silicate and ice. In general, the farther a satellite is from the sun, the higher is its percentage of ice. The majority of satellites consist mostly of ice. Most of the ice on satellites is water ice--like ordinary ice on Earth.
Many satellites appear rough, with craters dating from more than 3 billion years ago. Some satellites have changed geologically since then. These moons have a variety of surface features, including active volcanoes.
Only two satellites are known to have an atmosphere--Titan, which orbits Saturn, and Neptune's moon Triton. On the surface of Titan, the atmospheric pressure (pressure exerted by the weight of atmospheric gases) is 1.6 times greater than that of Earth. Triton's atmosphere is much thinner. Its surface pressure is only about 1/70,000 that of Earth.
Scientists use telescopes and spacecraft to study satellites and their parent planets. Spacecraft have flown close to all the planets except Pluto. Human beings have set foot on only one satellite--Earth's moon.
