Comments on: Circumstellar Disk Around a Massive Star http://www.centauri-dreams.org/?p=10424&utm_source=rss&utm_medium=rss&utm_campaign=circumstellar-disk-around-a-massive-star The News Forum of the Tau Zero Foundation Wed, 08 Sep 2010 01:18:34 +0000 hourly 1 http://wordpress.org/?v=3.0.1 By: Hubble revela a essência da nebulosa de Iris « Eternos Aprendizes http://www.centauri-dreams.org/?p=10424&cpage=1#comment-76431 Hubble revela a essência da nebulosa de Iris « Eternos Aprendizes Wed, 02 Dec 2009 14:11:37 +0000 http://www.centauri-dreams.org/?p=10424#comment-76431 [...] da Íris, mostra uma região repleta de poeira cósmica. Iluminada pela massiva estrela próxima HD 200775, com 10 vezes a massa do Sol, o pó lembra algodão doce, acentuado por estrelas-diamante. O [...] [...] da Íris, mostra uma região repleta de poeira cósmica. Iluminada pela massiva estrela próxima HD 200775, com 10 vezes a massa do Sol, o pó lembra algodão doce, acentuado por estrelas-diamante. O [...]

]]> By: Ronald http://www.centauri-dreams.org/?p=10424&cpage=1#comment-76429 Ronald Wed, 02 Dec 2009 11:31:32 +0000 http://www.centauri-dreams.org/?p=10424#comment-76429 @spaceman: in the extrasolar planets encyclopedia, I found an A3 (Fomalhaut), an A6 (beta Pictoris), and an A5 (HR 8799, with 3 super-giant planets in wide orbits!), furthermore rather many F stars. However, there are also quite a few K giants and subgiants (II and III). That there are so few A stars with (giant) planets may simply be observational (or rather populational) bias: they are quite uncommon. So I have no idea how this would work out relative to population size. What strikes me more is that so many K (sub)giants have planets, despite the fact that they are rare. I do not know whether this is a real phenomenon or the result of observational preference. I mean, are there any programs favoring K giants? @spaceman:
in the extrasolar planets encyclopedia, I found an A3 (Fomalhaut), an A6 (beta Pictoris), and an A5 (HR 8799, with 3 super-giant planets in wide orbits!), furthermore rather many F stars.

However, there are also quite a few K giants and subgiants (II and III).

That there are so few A stars with (giant) planets may simply be observational (or rather populational) bias: they are quite uncommon. So I have no idea how this would work out relative to population size.

What strikes me more is that so many K (sub)giants have planets, despite the fact that they are rare. I do not know whether this is a real phenomenon or the result of observational preference. I mean, are there any programs favoring K giants?

]]> By: Adam http://www.centauri-dreams.org/?p=10424&cpage=1#comment-76290 Adam Wed, 25 Nov 2009 22:51:45 +0000 http://www.centauri-dreams.org/?p=10424#comment-76290 Anthony Whitworth and colleagues have pondered for some time just how brown dwarfs formed and their favoured scenario involves a heavy disk around a large-ish star which then gravitationally fragments. Wonder if this star's disk is cool/massive enough to birth brown dwarfs? Anthony Whitworth and colleagues have pondered for some time just how brown dwarfs formed and their favoured scenario involves a heavy disk around a large-ish star which then gravitationally fragments. Wonder if this star’s disk is cool/massive enough to birth brown dwarfs?

]]> By: spaceman http://www.centauri-dreams.org/?p=10424&cpage=1#comment-76288 spaceman Wed, 25 Nov 2009 22:02:28 +0000 http://www.centauri-dreams.org/?p=10424#comment-76288 Indeed, it would be interesting to know whether or not stars this massive form planets. Related question: What is the most massive star known to have an extrasolar planet in orbit around it? Is it a spectral type A or F? Indeed, it would be interesting to know whether or not stars this massive form planets. Related question: What is the most massive star known to have an extrasolar planet in orbit around it? Is it a spectral type A or F?

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