• best visual representation of Betelgeuse?

    From Jay Taat@21:1/5 to All on Fri Sep 1 08:18:23 2023
    My son is in college and writing a paper on this unusual star after
    first becoming interested in it from the rather vague Hubble images.
    With it's more recent variability episodes, he's wondering what the star
    would actually look like up close (close meaning the equivalent of how
    our sun appears to us)? It almost certainly wouldn't be spherical I
    wouldn't think. Are there any illustrations that could be shared as to
    it's approximate appearance>

    thanks,
    Jay T

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  • From Martin Brown@21:1/5 to Jay Taat on Fri Sep 1 15:13:08 2023
    On 01/09/2023 13:18, Jay Taat wrote:
    My son is in college and writing a paper on this unusual star after
    first becoming interested in it from the rather vague Hubble images.
    With it's more recent variability episodes, he's wondering what the star would actually look like up close (close meaning the equivalent of how
    our sun appears to us)?  It almost certainly wouldn't be spherical I wouldn't think.  Are there any illustrations that could be shared as to
    it's approximate appearance>

    Not really. There are plenty of artist's impressions though.
    Some are a more fanciful than others.

    The highest resolution image to date is in the mm waveband from ALMA

    https://www.space.com/37344-alma-captures-clearest-image-of-betelgeuse.html

    It strikes me that with Doppler methods and the occasional bright
    feature on the surface there may be a guestimate of its rotation speed
    which together with its radius will determine how oblate it actually is.

    Our sun is a pretty good approximation to a sphere (rotates ~24-30 days) whereas Jupiter clearly is oval shaped (rotates every 8 hours or so).

    Wiki has quite a decent article on its apparent diameter as a function
    of observing wavelength.

    https://en.wikipedia.org/wiki/Betelgeuse#Diameter

    Several other big radius stars have been targets for indirect imaging or determinations of their diameters by optical interferometry. It has a
    long history going back to Michelson & Pease in the 1920's.

    https://www.mtwilson.edu/news/discovering-mount-wilson-chapter-11-the-stellar-interferometer/

    --
    Martin Brown

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  • From Jay Taat@21:1/5 to All on Sat Sep 2 13:26:46 2023
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    VA0K

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  • From RichA@21:1/5 to Jay Taat on Sat Sep 2 11:48:30 2023
    On Friday, 1 September 2023 at 08:18:27 UTC-4, Jay Taat wrote:
    My son is in college and writing a paper on this unusual star after
    first becoming interested in it from the rather vague Hubble images.
    With it's more recent variability episodes, he's wondering what the star would actually look like up close (close meaning the equivalent of how
    our sun appears to us)? It almost certainly wouldn't be spherical I
    wouldn't think. Are there any illustrations that could be shared as to
    it's approximate appearance>

    thanks,
    Jay T

    They did interferometry studies in the 1970s of Betelgeuse which showed the disk to be mottled. Quite the feat then.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)