最近，科学家在主小行星带中也发现了一些彗星——这些主带彗星可能是类地内行星上水的关键来源。

Recently, scientist have also discovered comets in the main asteroid belt -these main-belt comets might be a key source of water for the inner terrestrial planets.

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起先，天文学家们认为这种景象不过是所谓的“主带彗星”——即较为少见的轨道在小行星主带内的彗星。

At first, astronomers thought it might be a so-called "main belt comet" — a rare case of a comet orbiting in the asteroid belt.

youdao

起先，天文学家们认为这种景象不过是所谓的“主带彗星”——即较为少见的轨道在小行星主带内的彗星。

At first, astronomers thought it might be a so-called "main belt comet" — a rare case of a comet orbiting in the asteroid belt.

youdao