The Planets

Our solar system consists of the sun, eight planets, moons, dwarf planets, an asteroid belt, comets, meteors, and others. The sun is the center of our solar system; the planets, their moons, the asteroids, comets, and other rocks and gas all orbit the sun. Solar system formation began billions of years ago, when gases and dust began to come together to form the Sun, planets, and other bodies of the solar system. The eight planets that orbit the sun are (in order from the sun): Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. A belt of asteroids (minor planets made of rock and metal) lies between Mars and Jupiter. Beyond Neptune are the dwarf planets, Pluto and Eris and the Kuiper Belt (mainly comets). These objects all orbit the sun in roughly circular orbits. Our Solar System has 4 inner, rocky planets and 4 outer,gas giant planets. All the planets have moons except Mercury and Venus. All the planets orbit the Sun in an anti-clockwise direction. Earth has 1 moon Mars has 2 moons Jupiter has 63 moons Saturn has 59 moons Uranus has 27 moons Neptune has 13 moons. A list of all the moons can be found here As the planets rotate around the sun, they can be seen at different times of the year and at different times of the day; for example, In March, Mars is high in the sky and Saturn is in the constellation of Leo. Mercury and Venus can be seen in the morning just before sunrise. When you see Saturn through a telescope for the first time, it's truly wonderful Name Size Temp. Comp.& Atmospere Description Sun wider than 100 Earths ~10,000 degrees F gas A star at the centre of our Solar System...bigger than any planet Mercury third as wide as Earth - 4878km across -184 to 427C rock;CO2 grey surface covered with craters...really cold or really hot Venus almost as big as Earth.. 12,104km across 465C rock; thick acid clouds...volcanoes Earth 12,796 km -89 to 58C rock ; N2 + 02 water and air...from space it looks blue with white clouds Mars half as big as Earth..6,787 km -82 to 0C rock; CO2 red rocks...huge volcanoes and craters Jupiter 11 Earths across..142,000 km -150c liquid & gas..rocky core H2 He biggest planet...orange, red,yellow, brown, white..thin rings Saturn 9 Earths across..120,000 km -170c liquid & gas..rocky core is gold, brown & white...has beautiful rings Uranus 4 Earths across..51,118 km -200c gas with a rocky core greenish blue..also has thin rings Neptune 4 Earths across...49,528 km -210 gas with metal core blue clouds & dark rings Related sites: Note: Pages will open in a new browser window Windows to the Universe Universe Today The Sky - Calendar of events The Night Sky