Solve Your HR Diagram Problem with Expert Help - Tuugii

[Tuugii]

how to solve it?

thanks,
Tuugii

 

[Astronuc]

How about trying to write an equation for stellar evolution. One has a 1M (solar mass if I read the symbol correctly) leaving the main sequence at 20 L. What's the significance of that?

We ask students to provide some work and effort when asking for assistance.

 

[Tuugii]

thanks a lot. But what is the equation of evolution? if you can provide me a little more info on that, I think I can make it further.

Tuugii

 

[Astronuc]

Here are some useful notes on stellar lifetimes. I haven't gone through the details, but there appears to be some variation. It would be worthwhile to do a comparison.

THE MAIN SEQUENCE
http://www.astronomy.ohio-state.edu/~ryden/ast162_4/notes14.html
http://ftp.astronomy.ohio-state.edu/~pogge/Ast162/Unit2/mainseq.html

http://www.astronomynotes.com/evolutn/s8.htm

Star main sequence lifetime = [star's mass / star's luminosity] × 10¹⁰ years.
Star main sequence lifetime = 10¹⁰ / (star's mass)^{(p - 1)}, where p = 3 for stars more massive than 30 solar masses and p = 4 for stars less massive than 10 solar masses.


http://astronomy.swin.edu.au/cosmos/M/Main+Sequence+Lifetime (this page seems pretty good)

http://csep10.phys.utk.edu/astr162/lect/mainseq/mainseq.html

http://zebu.uoregon.edu/~imamura/208/feb6/life.html

Notes on Stars
http://www.astro.uiuc.edu/~kaler/sow/class.html