Giant And Supergiant Stars
By: Landon M.
What are giant and supergiant stars you may ask?
A giant star is a very large, bright non-main-sequence star that burns hydrogen at a much faster rate than a dwarf star. Giant stars are much more brighter and have shorter lifespans than the slower-burning dwarfs. The larger the giant, the shorter its lifespan is and the largest stars, with solar mass or around 100, shine at several hundred thousand times the energy of the Sun and will last only a few million years, a very brief time when compared with the Sun's 10-billion-year-lifespan. Giant stars usually end their lives as supernovae, but even before that event the powerful ultraviolet radiation they produce has a dramatic impact on their stellar surroundings; the presence of a giant star in a star system prevents formation of new protostars because the radiation from the giant star breaks apart any nearby nebulae.
A supergiant star is a star that is larger and brighter than a giant star, being thousands of times brighter than the Sun and having a relatively short lifespan only about 10 to 50 million years as opposed to around 5 billion years for the Sun. Supergiants, such as Betelgeuse and Rigel are only found in young cosmic structures such as spiral galaxies. Red supergiants such as Betelgeuse are late-stage stars, having burned most of their hydrogen in an earlier stage as main-sequence stars, and now fuse helium into heavier elements. Blue supergiants such as Rigel are thought to have evolved from red giants, though some are considered main-sequence stars. Supergiants are thought to eventually undergo a supernova, ending up as neutron stars or black holes.
More Details About Giant And Supergiant Stars
Sources
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- "supergiant". The American Heritage® Science Dictionary. Houghton Mifflin Company. 13 Dec. 2015. <Dictionary.com
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