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TorontoAstro101
2006-Nov-20, 05:41 PM
Hey guys -

I'm working on an astro project due tomorrow, and I need to find out the semi-major axes of Alpha Centauri A & B, Proxima, and Sirius A & B. I've tried Wikipedia and Google, and neither of them were of any help. Would any of you know?

Thanks.

TorontoAstro101

tony873004
2006-Nov-20, 06:02 PM
You're right, Wikipedia isn't too helpful answering this. You can find the answers in these links, which are both under the "References" section in the Wikipedia articles:

http://www.solstation.com/stars/alp-cent3.htm
http://www.astro.uiuc.edu/~kaler/sow/sirius.html

It is still not confirmed whether or not Proxima Centauri is bound to Alpha Centauri A and B. So it would not be possible to determine a semi-major axis when we don't even know if it has an orbit. It is roughly 12000 AU from the AB pair, so that might be the best you can do. But explain it like that. Don't call it a semi-major axis.