• davidgro@lemmy.world
    link
    fedilink
    English
    arrow-up
    6
    ·
    2 hours ago

    In my opinion Polaris B and Polaris Ab (it’s actually a three star system!) don’t count as ‘The North Star’ because they contribute almost nothing to the visible light seen without a telescope. Without Aa there’s just no north pole star at the moment.

    But that’s interesting about the age being uncertain. I’d use the age of the merger as the age of the star anyway unless it didn’t add much mass (but in that case it would have been a short lived giant anyway…) which would still likely put it under the 420 million years mark.

    • neatchee@lemmy.world
      link
      fedilink
      English
      arrow-up
      2
      ·
      edit-2
      48 minutes ago

      Fair enough on the first point!

      The interesting scenario re: Polaris A’s age would be if a larger, younger original star merged with a smaller, much older star. You’d have a small amount of late-stage byproducts in an otherwise relatively early-stage star. That would definitely make any age models ‘confused’ heh

      I could imagine a scenario where the math works out such that the star appears a lot younger than it is despite being the product of a merger of two older stars, based on the masses and ages of the contributing objects and the amount of different material contributed by each