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Name: Gregory R.
Status: other
Grade: other
Location: NV
Country: N/A
Date: N/A

Did any planet ever blow up?

Dear Gregory,

Planets do not blow up. About 3.9 billion years ago a Mars-sized protoplanet (you could call it young planet) collided with Earth, ripping off its crust. For about a year after the collision there was a thick ring about the Earth.

The particles, both from the Earth and the other planet, joined together within a year to form the Moon. Jupiter must have had this experience many times with other protoplanets. But a planet just blowing up? I doubt it.

David H. Levy


That would depend on what you mean by blow up. Research indicate that in the very early history of our solar system, there was a planet orbiting where Earth is now (let's call this planet: proto-Earth). Near this proto-Earth was another planet (let's call this planet: proto-Moon). Because proto-Earth and proto-Moon had orbits that brought them very close to each other, the two planets collided and smashed into each other. The force of this collision was so strong that it blew up both planets. However, since the blown up bits of both planets were still close to each other, the planets reformed into what is now Earth and the moon. The reason we know this is that the core of the Moon is very much like that of Earth and that is unusual. Also, unlike most moons that get closer to the planet that it is orbiting, our moon is getting farther away - which tells us that it used to be very close to the Earth.

Greg (Roberto Gregorius)

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