Jupiter is the king of the planets. It’s the biggest of the Sun’s eight major planets — about 11 times the diameter of Earth. And it’s more massive than all the other planets and moons combined. And right now, it really looks the part. It’s lining up opposite the Sun, so it’s closest and brightest for the entire year, and it’s in view all night.

Jupiter’s great heft means it must have been in the “sweet spot” for planet formation. It was close enough to the Sun that there was a huge supply of raw materials for making planets. And it was far enough that the mixture included a lot of ices. Small grains of ice, rock, and metal stuck together to make larger and larger chunks. The chunks then stuck together to form planets.

As Jupiter grew, its increasingly powerful gravity pulled in more and more of these building blocks. In addition, there was a lot of leftover gas from the formation of the Sun. The more massive Jupiter got, the more of this hydrogen and helium gas it pulled in. So today, Jupiter consists mainly of those two elements, with a melty core of heavier materials in the middle — making it the king of the Sun’s planets.

Jupiter is low in the east as night falls, arcs high across the south during the night, and is low in the west at dawn. It looks like a brilliant star. In all the night sky, it’s outshined only by the Moon and by Venus, which is ending its rein as the “morning star.”
 

Script by Damond Benningfield

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