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Author Topic: Why would dust vanish from around a star?  (Read 2138 times)

Offline thedoc

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Why would dust vanish from around a star?
« on: 28/08/2012 21:38:08 »
A huge, hot dusty disc around a Sun-like star seems to have vanished before our very eyes, and its disappearance cannot be explained by any current scientific theory.

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« Last Edit: 28/08/2012 21:38:08 by _system »


 

Offline Phractality

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Re: Why would dust vanish from around a star?
« Reply #1 on: 08/07/2012 23:21:17 »
We had only observed the disk of dust for 25 years, but we assumed it had been there for millions or billions of years. We also assumed that no planets had already formed around the star. So what if the disk was the result of a recent collision of pre-existing planets? Perhaps one or more large parts of the planets that collided were still orbiting within the dust cloud. This could have been similar to the collision between proto Earth and Theia, believed to have resulted in formation of our Moon.
 

Offline Lmnre

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Re: Why would dust vanish from around a star?
« Reply #2 on: 09/07/2012 15:30:58 »
A guess: The collision of particles dramatically transitions from elastic to inelastic due to the particles' state changing from solid to liquid/semi-liquid due to the star's radiation or other source, with the kinetic energy converting to thermal energy which accelerates/maintains the coalescence into a planet.
« Last Edit: 11/07/2012 22:00:11 by Lmnre »
 

Offline Geezer

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Re: Why would dust vanish from around a star?
« Reply #3 on: 10/07/2012 05:29:59 »
I suspect that Dyson guy had something to do with it.
 

Offline CliffordK

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Re: Why would dust vanish from around a star?
« Reply #4 on: 10/07/2012 09:53:53 »
Too bad that it doesn't sound as if there was a series of repeated observations. 

I would think that planetary formation would take far more than a decade or so.  If the dust cloud had a stable orbital velocity, then it should take a long time for all of it to coalesce into a planet.  If it had zero orbital velocity, then it might rapidly fall back to the star.  Consider that it takes Jupiter a decade to just circle the sun once, let alone vacuuming up stuff in its path (or in British....  Hoovering up the dust).

Is it possible that there was a HUGE Coronal Mass Ejection (CME), that would either fall back into the star, or continue moving out into very cool (and rarefied) regions of space.  What would happen if a large planet collided with a star?
 

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Re: Why would dust vanish from around a star?
« Reply #4 on: 10/07/2012 09:53:53 »

 

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