New research pins down Jupiter's size, spin, and magnetic state during the solar system's formative years, providing vital clues to planetary formation.
    • WoodScientist@sh.itjust.worksEnglish
      16·
      4 个月前

      Considering it would have to be an order of magnitude larger just to fuse deuterium? No. The smallest brown dwarfs are 13x Jupiter’s mass. And this article describes only a change in Jupiter’s size, not its mass.

      • The Bard in Green@lemmy.starlightkel.xyzEnglish
        3·
        4 个月前

        The article doesn’t say it (it actually doesn’t explain anything very well), but the implication to me seems to be that Jupiter was much hotter in the past, shrinking (and becoming less magnetically active) as it cooled?

        I imagine this has implications for aging gas giants. What will Jupiter be like in a billion years?

      • muhyb@programming.dev
        2·
        4 个月前

        Thanks for the explanation. So it has to be 13x of its mass to be considered as a failed star. This astonishes me, we are so insignificantly small. Hmm, can we assume it just got dense in time then?

        • WoodScientist@sh.itjust.worksEnglish
          7·
          4 个月前

          Gas giants get denser with time. They’re, by definition, mostly made of gas. And gas significantly expands or contracts based on temperature. I’m sure a terrestrial planet like Earth shrinks slightly as it’s cooled from its founding, but nothing compared to a gas giant. Jupiter was much hotter earlier on. So as it cooled, it became less puffed up.

          • muhyb@programming.dev
            3·
            4 个月前

            I see. Its core temperature is closer to a planet than a brown dwarf I guess. Though I have found this. Well, space is amazing.