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Brown Dwarf Star

October 14, 2011 by · Comments Off on Brown Dwarf Star 

Brown Dwarf StarBrown Dwarf Star, A new study has appeared more than two dozen stars failed, including light only about six times the mass of Jupiter one.
The discovery could shed light on these strange objects known as brown dwarfs, which straddle the boundary between stars and planets.

 
Brown dwarfs do not accumulate enough material, and therefore the mass to start nuclear fusion process that makes the stars shine like our Sun
Astronomers using the Subaru telescope in Hawaii and the Very Large Telescope in Chile for optical and infrared observations of two young star clusters, the search for brown dwarfs.
The study, which has been accepted for publication in the Astrophysical Journal. A paper focused on the star cluster NGC-1333 which is 1000 light years away in the constellation Perseus.
The astronomers found that one third of the stars in the cluster were actually brown dwarfs, which raises questions about the type of environmental conditions necessary to foster the development brown dwarf.

They also found one of the least massive brown dwarf ever detected. Despite being the size of a large planet, which orbits a star, raising questions about how it formed.
Stars form from the collapse of molecular gas and dust clouds, while the planets were formed from the protoplanetary disks of material left over from star formation.
Scientists believe that most brown dwarfs form like stars, however, small brown dwarfs form like planets around a star and then ejected into interstellar space.
“The results suggest (Earth-sized) objects not much larger than Jupiter might form stars in the same way they do,” says lead researcher Professor Ray Jayawardhana of the University of Toronto.
“What’s more, a remarkable cluster contains a surplus of these, half received many such astronomical oddball as normal stars.”
“In other words, nature seems to have more than one trick up its sleeve for producing planetary mass objects.”
The paper examines the Rho Ophiuchi star cluster, 460 light-years away in the constellation Ophiuchus.
The scientists discovered six new brown dwarfs, which represents a fifth of the population known star in the cluster.

Dr Fred Watson from the Astronomical Observatory of Australia says that the papers suggest the brown dwarfs may be more common than previously thought.
“The work sheds new light on the kind of conditions in which brown dwarfs form,” says Watson.
“If the gas pressure in these environments is high enough, which could have an impact on the type of objects is developing.”
“We also push down the lower limit for the mass of brown dwarf star, it was believed that at least 13 times the mass of Jupiter. Such a figure is established due to the burning of deuterium, which feeds the brown dwarf, falls below this point. ”
“This further obscures the boundary between what we call stars and planets what we define as” he adds.

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