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Gamma Orionis (Bellatrix)

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Gamma Orionis (Bellatrix)

Posted by Astrid Ohlmeier at 12:51 on 2012 Feb 20

Hi Deep Sky MembersI have a question about Gamma Orionis (Bellatrix), the blue-white giant B Star in Orion. If the star has a planetary system, could there be life on one of the planets, which could be a good distance away? The new Kepler space telescope can be pointed to Bellatrix to confirm the existence of a planetary system. Or do you think the star is too bright to detect planets?RegardsAstrid

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Re: Gamma Orionis (Bellatrix)

Posted by Paul A Brierley at 06:57 on 2012 Feb 22

Hi Astrid,The only way we'll know, whether Bellatrix has a planet, or planets. Is by observations using the transit method.Where, you watch the star dim, as a planet transit's the solar disk.Kepler isn't able to see this region of sky, because it is pointing at a small patch of space in Cygnus.The chances of there being life on such a planet. Your guess is as good as mine.But I would like to think so...

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Re: Gamma Orionis (Bellatrix)

Posted by Astrid Ohlmeier at 11:43 on 2012 Feb 22

Thanks for the infos, good to know where Kepler is pointing.

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Re:Gamma Orionis (Bellatrix)

Posted by D Gray at 16:17 on 2012 Feb 22

Hi Astrid,For all we know stars like Bellatrix could have a huge retinue of planets. But I believe current thinking is that such hot stars are liable to blow the dust and gas away before they get the chance to form?? As it has a mass up to nine times solar it is destined to become a red giant and then white dwarf (just escaping going supernova) in a time-span that may not give life much opportunity to develop/evolve.Check this link out: http://stars.astro.illinois.edu/sow/bellatrix.html Given that it has some six times the suns diameter any transiting planet would need to be huge to cause a measurable dip in its light. Also a life-bearing body would have to be pretty far out, thus having a very long orbital period giving quite infrequent transits.Fascinated to know why you singled out this particular star a favourite perhaps? Rigel is one of mine but the prospects for planets and life there look very dire indeed but nature just keeps on surprising us!Regards David.

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Re:Gamma Orionis (Bellatrix)

Posted by Paul A Brierley at 17:41 on 2012 Feb 22

I still find it difficult to believe that Earth is unique.And I hope one day in the not to distant future. Kepler or another planet finding mission. Will finally detect, another Earth.Does anybody here know whether the TSP (Terrestrial Planet Finder) got off the drawing board?I believe this was quite an ambitious project, that would. It was hoped. Search and even image, a terrestrial planet?