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Non-Spherical Stars

Posted by michael on from the first-you-assume-a-spherical-cow dept.

An anonymous reader writes "Now that the large interferometers are coming on line, the stars are no longer dots. Achernar (Alpha Eridani), is a huge ellipsoid whose polar radius (due to fast spinning) is 50% smaller than the equatorial one!"

2 of 70 comments (clear)

  1. Energy output by VendingMenace · · Score: 4, Interesting

    50% smaller? Wow, this must be spinning incredibly fast. With so must mass being displaced from where it would be in a sphere, it must effect the pressure inside the star. As such, i wonder how much this effects the fusion within the star. Since fusion is driven by the compressional forces of the suns mass, the effective reduced mass must reduce the energy output of this star. RIght?

    Perhps i don't really kow what i am talking about.

  2. Re:Theoretical maximum for common stellar material by CheshireCatCO · · Score: 4, Interesting

    I believe a star has zero tensile strength* (it's just a fluid), so once you're spinning too fast for gravity to hold you together, it's bye-bye time.

    The better question is this: how did that star form? If it was spinning too fast to hold together, how did it accrete matter with that much angular momentum at all?

    * Barring magnetic fields, mind you. But you'd need an ass-kicking field to hold a star together very long, I would think.