Thread

1. jahnu · 1789828933 · focus · HN ↗

   One thing worth noting is our popular notion of what a star seems to be is quite different from what astronomers have.

   One example, Canis Majoris has a radius of about 1420 solar radii. But its mass is roughly 17±8 times the mass of the Sun and therefore an average density of 5.33 to 8.38 mg/m3. “It is over 100.000 times less dense than Earth’s atmosphere at sea level.”

   <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;VY_Canis_Majoris" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;VY_Canis_Majoris

   <a href="https:&#x2F;&#x2F;nineplanets.org&#x2F;vy-canis-majoris&#x2F;" rel="nofollow">https:&#x2F;&#x2F;nineplanets.org&#x2F;vy-canis-majoris&#x2F;

   1. usrnm · 1789829484 · focus · HN ↗

      My layman definition of what a star is is &quot;it&#x27;s somewhere in the sky and it gives off light&quot;. The word &quot;density&quot; wouldn&#x27;t even come to my mind

      1. kulahan · 1789855188 · focus · HN ↗

         Thanks to blackbody radiation, every human skydiver briefly becomes a star by this definition! ;)

         It needs a core generating energy through fusion, which has density requirements, for what it’s worth.

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