(Solved) How long does a typical star spend in the main sequence?

You can infer how long a star of a given mass will be on the Main Sequence, which is the stage of life where a star fuses hydrogen into helium for energy. It has also been determined that all stars spend some 80 or 90 percent of their active lifetimes as Main Sequence stars generating their own energy internally. How long a star lasts as a Main Sequence object is directly dependent upon it's mass and to a much lesser degree the chemical composition it started it's life with. The more massive the star, the less time it can last as a Main Sequence object. As the mass increases, the surface temperature, the diameter and the luminosity also increases. The more massive a star, the more violently it's death will be. As for what a typical star is, it's most certainly not a blue giant such as Rigel, nor is it a star like the Sun or Alpha Centauri A. It's a red dwarf, which comprise some 75 percent of all stars. The Sun was born with enough fuel to spend 10 billion years or more on the Main Sequence, but the average red dwarf will last a trillion years even though it could be less than 20 percent of the Sun's mass. They are long lived because the pressure in their cores is barely enough to start and maintain nuclear fusion, and thus they do not have to generate much energy to support themselves against their own gravity. Massive stars have to generate huge amounts of energy to oppose their own gravity, and thus rapidly exhaust their fuel even though they can start out with 100 times the Sun's mass. This results in a luminosity that can exceed the Sun 50,000 times over, but also results in a life span of a mere 10 million years or less.

Home Search Q & A Board Gallery Resource Library Blog Dictionary Chat	Quick Links Start a Topic Latest Topics Unanswered Questions Courses Study Tools Browse by Textbook	Social Facebook YouTube Community Stats Who's Online Trending Staff	Help About Us Take the Tour Study Tips Posting Guidelines Terms and Policies Contact Us
Biology Forums - Study Force © 2010-2024 \| Powered by SMF \| SMF © 2015, Simple Machines \| Sitemap Biology-Forums.com is not affiliated with any publisher. Book covers, title and author names appear for reference only.

How long does a typical star spend in the main sequence?

Related Topics