Mercury is a planet that just doesn’t make sense. It’s incredibly small yet hosts a relatively massive core. Mercury is so strange that astronomers have not been able to explain its properties with simulations of the solar system’s formation. But now, researchers have found an important clue, and Mercury’s weirdness appears to be the fault of the giant planets.
https://www.space.com/mercury-weird-because-of-jupiter-outer-planets
Basically, Mercury is nearly as dense as the Earth despite being less than 6% the size. This is due to the gas giants in our solar system yanking material (“planetesimals” and protoplanets) and ejecting it from the solar system, leaving Mercury with very little material left to form itself.
But there are plenty of questions still…
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