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ToSeek
2005-Jan-20, 06:03 PM
Discovery challenges theories on brown dwarfs (http://www.spaceflightnow.com/news/n0501/20browndwarfs/)


Although mass is the most important property of stars, it has proved very hard to measure for the lowest mass objects in the universe. Thanks to a powerful new camera, a very rare, low-mass companion has finally been photographed. The discovery suggests that, due to errors in the models, astronomers have overestimated the number of young "brown dwarfs" and "free floating" extrasolar planets.

parallaxicality
2005-Jan-20, 07:49 PM
Interesting. I remember a small article a few years ago that said that astronomers weren't finding many red dwarfs either, which was strange because I remembered reading a number of books which claimed that red dwarfs were the commonest stars in the galaxy. Perhaps mid-to-large stars are more easily formed. Is it possible, perhaps, that larger stars are actually those most often formed, but that their short lifespans means that at any one time we see fewer of them then we should?

synthomus
2005-Jan-20, 09:31 PM
If proved true it would mean there is less of menacing free floating dark stuff around. Good for long term stable planetary orbits in solar systems anywhere. Sigh, what a relief! 8-[

tjm220
2005-Jan-20, 10:07 PM
The article claims that brown dwarfs are objects that are 75 Jupiter masses. I thought the minumum mass was more like 13 Jupiter masses. So that object is 93 Jupiters. Is this enough mass to make it a star then, a really dim M class star?

eburacum45
2005-Jan-21, 06:28 PM
I have to say I love the name of this object: AB Doradus C,
also known as
AB Dor C

(the way it is written it looks like they couldn't make their mind up.)