main sequence

A Dictionary of Astronomy | 1997 | 700+ words | Copyright

main sequence A diagonal strip on the Hertzsprung–Russeu diagram, from top left to lower right. A star is said to be on the main sequence at the stage of its life when it shines by converting hydrogen to helium at its centre. A star's position on the main sequence depends on its mass, with the most massive stars at the upper left and the least massive at the lower right. The Sun, an average star, lies about half-way along the main sequence. Whatever its mass, a star on the main sequence is termed a dwarf. Stars spend most of their lives on the main sequence, remaining at roughly constant temperature and luminosity, but the time they spend there depends on their mass. For very massive stars, the main-sequence stage lasts only about a million years, but for the least massive stars it is potentially longer than the age of the Universe. See also Zero-Age Main Sequence.

Cite this article
Pick a style below, and copy the text for your bibliography.

MLA
Chicago
APA

"main sequence." A Dictionary of Astronomy. 1997. Encyclopedia.com. 30 May. 2012 <http://www.encyclopedia.com>.

"main sequence." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 30, 2012). http://www.encyclopedia.com/doc/1O80-mainsequence.html

"main sequence." A Dictionary of Astronomy. 1997. Retrieved May 30, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-mainsequence.html

Learn more about citation styles