7 comments

  • mturk 39 minutes ago
    MESA, a piece of software referenced in this article, is a pretty incredible system. (Even referring to it as software underplays the extent of its community and impact.)

    Many people are involved in MESA and Bill Paxton was always quick to point out the many new folks that worked on it, but this article does a great job of celebrating his impact:

    https://www.kitp.ucsb.edu/news/an-accidental-astrophysicist

    It's amazing to me that he went from being the voice on the other end of the Mother Of All Demos to having such a major impact on stellar astrophysics during his "retirement." He passed away in 2025.

  • jcims 7 minutes ago
    You have to get nearly halfway from the surface of the sun (photospere) to its core before the density of the sun’s material is equivalent to that of the earth.
  • A_D_E_P_T 2 hours ago
    > Their results favour a scenario in which the young Sun engulfed a super-Earth around 5–10 times the mass of Earth

    Given the state of the early solar system, it would be surprising if the Sun didn't swallow a lot of metallic and carbonaceous rocks and pebbles. But it seems unclear to me how the researchers would distinguish between one super-Earth and >10^10 smaller rocks? Chemically I feel the two would be largely the same.

    • cfiggers 2 hours ago
      That's easy, they'll check whether there's one big fingerprint vs >10^10 little tiny fingerprints and conclude accordingly \j
      • amelius 55 minutes ago
        Not if the EU has a say about it. Those rocks and pebbles have a right to privacy and fingerprinting is off the table.
    • hydrogen7800 47 minutes ago
      >But it seems unclear to me how the researchers would distinguish between one super-Earth and >10^10 smaller rocks?

      I have a similar feeling when life on earth is suggested to be "alien", arriving via debris in the solar system as the earth formed. Isn't everything in the solar system coalesced from the same debris?

      • jojobas 40 minutes ago
        The life-bearing debris would have to arrive quite some time after formation of Earth, as it was molten. Surviving atmospheric entry is hard, surviving after landing in lava is impossible.
        • hydrogen7800 16 minutes ago
          I was going to expand on my comment about the difference between alien and non-alien being a difference only in time. It's all from the same stuff.
        • gohomeloser 38 minutes ago
          [dead]
    • bell-cot 1 hour ago
      This, but how do they rule out the extra stuff landing in the sun much earlier - when the solar system was still a pre-solar nebula, and which bits would end up where (sun vs. planets vs. whatever) was far from settled?
    • omnicognate 2 hours ago
      > Researchers also found that such a world could survive its passage through the Sun's outer layers while losing very little mass, which suggests that planets may leave detectable fingerprints inside their host stars long after they have disappeared.

      So I guess the large size would have permitted it to smuggle stuff into the core that would have just vaporised in the corona if carried by many smaller objects?

      • monster_truck 25 minutes ago
        Sounds reasonable to me.

        But also what the fuck happens to the core of such a planet when that happens?

        We aren't actually sure what gave our core the spin it has, right? I'm not fully awake yet but I think it's plain where I'm going with this.

  • N_Lens 2 hours ago
    That’s it Apollo! Spit it out, what’s in your mouth, spit it out now!
  • hnd9q09qk4 1 hour ago
    Did stellar abundance fits in grad school, getting the Teff systematics out took months.
  • run-good-code 1 hour ago
    When I saw the word 'Fingerprints', I thought it was a brilliant expression.
  • Martin_Silenus 1 hour ago
    I once ate a peanut too.