Editing Star (section)

===Temperature===
The surface temperature of a main sequence star is determined by the rate of energy production of its core and by its radius, and is often estimated from the star's [[color index]].<ref name="astronomynotes">{{cite web
 |url=http://www.astronomynotes.com/starprop/s5.htm
 |title=Properties of Stars: Color and Temperature
 |access-date=2007-10-09 |last=Strobel |first=Nick
 |date=2007-08-20 |work=Astronomy Notes
 |publisher=Primis/McGraw-Hill, Inc.
 |archive-url=https://web.archive.org/web/20070626090138/http://www.astronomynotes.com/starprop/s5.htm
 |archive-date=2007-06-26}}</ref> The temperature is normally given in terms of an [[effective temperature]], which is the temperature of an idealized black body that radiates its energy at the same luminosity per surface area as the star. The effective temperature is only representative of the surface, as the temperature increases toward the core.<ref>{{cite web
 | first=Courtney | last=Seligman | work=Self-published
 | url=http://cseligman.com/text/stars/heatflowreview.htm
 | title =Review of Heat Flow Inside Stars
 | access-date= 2007-07-05}}</ref> The temperature in the core region of a star is several million [[kelvin]]s.<ref name="aps_mss" />

The stellar temperature will determine the rate of ionization of various elements, resulting in characteristic absorption lines in the spectrum. The surface temperature of a star, along with its visual [[absolute magnitude]] and absorption features, is used to classify a star (see classification below).<ref name="new cosmos" />

Massive main sequence stars can have surface temperatures of 50,000&nbsp;K. Smaller stars such as the Sun have surface temperatures of a few thousand K. Red giants have relatively low surface temperatures of about 3,600&nbsp;K; but they have a high luminosity due to their large exterior surface area.<ref name=zeilik>{{cite book |last1=Zeilik |first1=Michael A. |last2=Gregory |first2=Stephan A. |title=Introductory Astronomy & Astrophysics |edition=4th |date=1998 |publisher=Saunders College Publishing |isbn=978-0-03-006228-5 |page=321}}</ref>