The Lyot Project
AB Aurigae, a star that is 470 light years away, is still surrounded by the dusty detritus out of which it formed.
Posted on 03/29/2008 11:42:49 PM PDT by neverdem
Is this a planet in the making?
A gap in the dust circling a young star in the constellation Auriga may mark where material is condensing into a planet, 11 astronomers led by Ben R. Oppenheimer of the American Museum of Natural History say in a paper to be published in The Astrophysical Journal.
The group used an Air Force surveillance telescope at Haleakala Observatories on the Hawaiian island of Maui and a special camera to examine a region near the star AB Aurigae, corresponding to the scale of our own solar system, that had not been observed before at high resolution. The results, they said, provided new insight into the process of planet and star formation.
The star is about 470 light years away and, being only about one million to three million years old, is still surrounded by the dusty detritus out of which it formed. In the picture, which shows the intensity of so-called polarized light scattered off dust particles, there is a gap about nine billion miles from the star, roughly three times the distance from Earth to Neptune.
Intriguingly, there is also what Dr. Oppenheimer and his colleagues call a “low significance detection” of a bright dot in the gap. If real, it could either be dust condensing on some object, Dr. Oppenheimer explained, or the object itself, which, based on its age and brightness would be 5 to 37 times the mass of Jupiter. That would put it on the dividing line between a planet and a kind of failed star called a brown dwarf.
“It does seem to be there,” Dr. Oppenheimer said in an interview.
Alan P. Boss, a planetary theorist at the Carnegie Institution of Washington, urged caution, noting that the astronomers “are trying something very difficult.”..
(Excerpt) Read more at nytimes.com ...
Perhaps we should ask Brian May from the band Queen?
No relation to J. Robert?
Cheers!
That would put it on the dividing line between a planet and a kind of failed star called a brown dwarf.
A "Brown Dwarf"? Oh-oh.
The professional wing of the Perpetual Victim Squad (aka PVS) are preparing their marches now (whew, at least 'niggardly' isn't mentioned too, there'd be riots).
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When a star is formed what happens? Does it reach a particular mass and then just turn on like a light switch?
or does it slowly get hotter and brighter?
IIRC, under the influence of gravity matter gets more dense until you get a critical mass. That's the tipping point. That's when nuclear fusion starts and is self sustaining. The energy released can grow until it hits a more or less steady state, like the Sun with its variations. Any corrections are appreciated.
The Wiki article: http://en.wikipedia.org/wiki/Stellar_evolution , seems to be pretty well written. Gases condense, getting hotter via simple thermodynamics, become brown dwarfs, which may fuse at least some deuterium-deuterium. This is a relatively “common” state for lightweight stars. If massive enough, the collapse can continue further to time when hydrogen can start fusing. Though it’s not mentioned in the article, I suspect that may well be close to a “light switch” regime: several percent in mass (given similar composition) may delineate too small to remain compressed despite additional internal pressure outward added by that fusion, from the stars massive enough to continue their collapse. It is probably a very small window of mass that will resist collapse, or even “oscillate” - I’ve never seen suggestions of the latter occurring.
I don’t recall seeing any data regarding this, though, and would love to hear from someone involved in the field. It is too bad we don’t have RadioAstronomer around any more due to The Purge. He would surely know, or be able to obtain, the answer for us.
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LOLOLOL, that’s quite a ‘fight’ going on there!!
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I also out the “Sphere” .gif in there - it’s 3 frames in that graphic
I am having trouble locating it because there are a lot of things that flicker in the graphic. Is it small and over one of the lights on the spaceship?
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