Jupiter is the fifth planet from the Sun and by far the largest planet in our solar system. Since it is much further from the Sun, Jupiter is much colder than the Earth. The average temperature on Jupiter is about -145 degrees Celsius. Most of the heat found on Jupiter is generated from the core of the planet, not from the Sun. The specific temperatures on Jupiter are relative to the distance away from the core. Remember that there is no real "surface" on Jupiter. It is a gas giant that is made mostly of hydrogen. There is no rocky surface like on Earth or Mars. The temperatures can vary between -160 and -100 degrees C depending on the altitude. The outer layer of Jupiter's atmosphere, however, is called the thermosphere and is located about 600 miles above the surface. The temperatures here can reach 725 degrees C.