● Betelgeuse

  Betelgeuse is a star in Orion.

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  Type            Red supergiant
  Constellation   Orion
  Magnitude       0.5
  Spectral type   M1-2Ia-Iab
  Distance        about 428 light years
  Double star     components 174.4″ apart
  You need        naked eye from a dark sky

  Known as
  Bayer           α Ori
  Yale            HR 2061

  Physical
  Radius          about 700 times the Sun, past the orbit of Mars

  More information about Betelgeuse

  Betelgeuse is so large that, if it replaced the Sun, its surface would
  reach past the orbit of Mars. It will explode as a supernova at some
  point in the next hundred thousand years, and when it does it will be
  bright enough to read by. It is also the most famous typo in the sky.
  The Arabic name was يد الجوزاء, Yad al-Jawza', "the hand of Jawza", and
  the initial ي, "ya", was read as ب, "ba", by medieval scribes who could
  not read Arabic and were working from letters that differ only in where
  the dot sits. That gave بط الجوزاء, Bat al-Jawza', which means nothing
  in any language, and then Bedalgeuze in the Alfonsine Tables of about
  1250.

  History
  First photographed   1995, Hubble, the first star other than the Sun resolved as a disc

  Etymology
  From                 Arabic
  Reading              Yad al-Jawza'  ·  يد الجوزاء
  Literally            hand of Jawza

  ┌ Greek · Ptolemy, 150
  │ he tou omou, the one on the shoulder
  │ ἡ τοῦ ὤμου
  │
  ├ Arabic · 9th c.
  │ Yad al-Jawza', hand of Jawza
  │ يد الجوزاء
  │
  ├ ✕ c.1100
  │ ya read as ba, one dot moved
  │ ي  ب
  │
  ├ Arabic
  │ Bat al-Jawza', which means nothing
  │ بط الجوزاء
  │
  ├ Latin · c.1250
  │ Bedalgeuze, Alfonsine Tables
  │
  └ English · now
    Betelgeuse

  Bayer lettered the stars of each constellation in his Uranometria of
  1603, in order of brightness. He was working from Tycho's magnitudes by
  eye, and the order he recorded is often wrong.

  First published in 1930 by Yale astronomer Frank Schlesinger, and
  maintained since, the Yale Bright Star Catalogue lists every star down
  to magnitude 6.5. It contains 9,110 stars.

  where it is tonight:  skymap.sh/Betelgeuse