Jupiter has a mass of about 1.9 x 10²⁷kg – 1900 trillion Trillion kilogrammes.  That’s more than double all the other planets, asteroids, comets and dust of the entire Solar System put together.  Jupiter is BIG, yet still manages to not weigh anything at all.  How?  Because it is in orbit around the Sun, just like an astronaut orbits the Earth, and so experiences zero gravity.  That’s not to say there is no gravity around Jupiter – it has plenty gravity of its own and anything moving with it will be drawn powerfully down towards Jupiter’s centre.  But it still moves freely in space without falling anywhere, and it’s the force with which something tries to fall that defines its weight.

Written by Allen Versfeld

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