Betelgeuse

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The pink arrow at the star on left labelled α indicates Betelgeuse in Orion

Betelgeuse, or Betelgeux is a large red supergiant star in the constellation Orion. It is the ninth-brightest star in the night sky, and second-brightest in Orion.

Betelgeuse is a semiregular variable star whose apparent magnitude varies between 0.2 and 1.2.[1] This is the widest range of any first-magnitude star. It is also one of the largest and most luminous observable stars. Its distance from Earth was estimated in 2008 at 640 light-years, with a mean absolute magnitude of about −6.02.[2]

Less than 10 million years old, Betelgeuse has evolved rapidly because of its high mass.[3] It is moving through the interstellar medium at a supersonic speed of 30 km/s, creating a shock wave over 4 light-years wide.

Betelgeuse is in a late stage of stellar evolution. It will rapidly go through its life cycle before exploding as a type II supernova sometime in the next million years. An observation by the Herschel Space Observatory in January 2013 showed that the star's winds are crashing against the surrounding interstellar medium.[4]

Related pages[change | change source]

References[change | change source]

  1. Davis, Kate (AAVSO Technical Assistant, Web) 2000. Variable star of the month: Alpha Orionis. American Association of Variable Star Observers (AAVSO). [1]
  2. Harper, Graham M. et al. 2008. A new VLA-Hipparcos distance to Betelgeuse and its implications. The Astronomical Journal 135 (4): 1430–40. [2]
  3. Levesque E.M. 2010. The physical properties of red supergiants. Astronomical Society of the Pacific. 425 Hot and Cool: Bridging Gaps in Massive Star Evolution ASP Conference Series: 103. [3]
  4. "Betelgeuse braces for a collision". ESA. 2013-01-22. http://www.esa.int/Our_Activities/Space_Science/Betelgeuse_braces_for_a_collision. Retrieved 2013-01-23.