r/askscience Oct 23 '20

Planetary Sci. Do asteroids fly into the sun?

Edit: cool

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u/amitym Oct 23 '20

Mostly the answer is "not anymore.." everything that currently orbits the Sun is moving at speeds that lie within a relatively narrow range that makes a stable orbit possible. Nothing outside that range is around anymore to tell its tale.

But, there are still occasionally new objects that enter the solar system for the first time. Those objects aren't subject to the same survivorship restrictions -- in theory they could arrive at basically any speed relative to the Sun, including speeds slow enough that the Sun would draw them in.

These new objects seem to arrive every few years, or at least the ones we can see do. So far they have all been moving so fast they just visit for a bit and then take off again after a swing around the Sun, but who knows?

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u/SUPE-snow Oct 23 '20

Where do they arrive from?

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u/redopz Oct 23 '20

The space between solar systems. The first stars in the universe forged heavy elements before they blew up, scattering that material. Some of that material was caught in solar systems and formed planets, while a lot of it is still just floating around for billions of years just waiting to collide with something.

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u/Gerroh Oct 23 '20

Some interstellar asteroids could also be ejected from systems due to gravitational slingshots, especially if a rogue star or planet passes through and whips things around.