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Since there is a continual loss of micrometeoritic material in space because of the radiation effects, there must be a continual replenishment: otherwise, micrometeorites would have disappeared from interplanetary space.

There are several possible sources.

According to Whipple ( 1955 ), cometary debris is sufficient to replenish the material spiraling into the sun, maintaining a fairly steady state.

Asteroidal collisions are also thought to contribute material.

It is also possible that some of the dust in the vicinity of the Earth originated from meteoritic impacts upon the moon.