Comets that have hit Earth have been a mixed bag. Early in Earth's history, during the solar system's chaotic beginning, they were likely the source of our planet's water, ultimately making up about 0.02% of the planet's mass. (Mars and Venus received a similar fraction.)
  • Onno (VK6FLAB)@lemmy.radioEnglish
    5·
    17 hours ago

    For anyone wondering like I did, that image is not what the headline suggests:

    An ultraviolet image of the train of Shoemaker-Levy 9 comet fragments impacting Jupiter’s atmosphere in 1994. The black dot near the top is Jupiter’s moon Io. Credit: Hubble Space Telescope Comet Team, NASA

    Source: the linked article.