Posted on 06/04/2007 6:39:29 PM PDT by KevinDavis
If were finding planets in places 1500 light years away, as the TrES project just did, why dont we know more about planets in the Alpha Centauri system? One problem is that Centauri A and B are relatively close to each other, with a semimajor axis of 23.4 AU. Leaving Proxima Centauri out of the picture (at 12,000 AU, its short-term effects can be disregarded), its still true that radial velocity studies have to take the complicated and varying spectra that binaries produce into account.
In other words, getting a read on binaries like these in terms of the slight wobbles that signal a planetary presence can consume lots of telescope time. Nonetheless, we do have some data thanks to observations with the Anglo-Australian Telescope. And weve learned this: No planet around either Centauri A or B induces a velocity variation as high as 2 meters per second. The implication is that any planet orbiting either star individually (in what is known as an S-type orbit) has to have a mass less than that of Saturn. Or if it is larger, and this is still possible, it must orbit in a plane that is substantially inclined to the line of sight to the system.
(Excerpt) Read more at centauri-dreams.org ...
I thought she was from Orion.
LOL!
She gets around.
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