Jupiter is the largest planet in the Solar System. It's also one of the largest planets in the Universe. There are planets out there with much more mass, but thanks to gravity, they are generally denser , not "bigger."

This raises an interesting question about massive exoplanets. Do they look similar to Jupiter? A new study finds they probably don't.

Before getting into the details, let's talk about the difference between a planet, a brown dwarf, and a star.

Very broadly, a planet is massive enough to compress into a sphere under hydrostatic equilibrium but not massive enough to trigger any kind of nuclear fusion in its core.

Stars are massive enough to trigger the fusion of hydrogen.

Brown dwarfs lie in the middle ground. They are too small to trigger

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