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This is only sort of true, unfortunately. Polaris is a two-star system: Polaris Aa and Polaris B.

Polaris B is much older than sharks, by several billion years.

Polaris Aa appears to be younger than sharks, at a measley 50 million years old, compared to sharks’ 420 million years

HOWEVER it is unclear whether Polaris Aa is actually that young. Scientists believe that, based on some contradictory findings, that measurement may be inaccurate if Polaris Aa is formed from two different stars that merged. In that scenario, the model we use to calculate star age would no longer work and could give wildly inaccurate estimates of the star’s true age

TMYK

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homesweethomeMrL@lemmy.world ⁨1⁩ ⁨month⁩ ago
Right but how did it know to be the pole star?? Huh?

Yeah! Makes ya think!

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davidgro@lemmy.world ⁨1⁩ ⁨month⁩ 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.

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- neatchee@lemmy.world ⁨1⁩ ⁨month⁩ 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 early-stage star. That would definitely make any age models ‘confused’ heh
  
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