Are the asteroids the remains of a planet which broke apart?

I have recently been introduced to the thought that the asteroid belt between Mars and Jupiter are the remains of a planet named Astera which had fragmented before it was able to solidify. Could you please forward any information you may have on this subject. Thank you for your time.....

Off and on, people suggest that the asteroid belt is the remains of a planet which either disintegrated or never quite got put together right.

On the other hand, the total mass in the asteroid belt is only about 1/4 the mass of the Moon, if even that much. Most of that mass, in turn, is in the largest 5 asteroids. Even if all the asteroids were to get together and form a planet, that "planet" would still just be an asteroid by our standards.

Moreover, the chemical makeup of the asteroids indicates that they were not all once part of a single body, but formed as a very large number of smaller bodies, some of which did later break apart to form even smaller bodies.

So, the answer I think is "no." Even if all the asteroids had come from a single parent body (the evidence is that they didn't), that parent body would be too small to be called a planet.

January 1999, Dave Kornreich (more by Dave Kornreich) (Like this Answer)

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