Brown Dwarfs Win Star Status

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Brown Dwarfs Win Star Status <br /><br />LINK<br /><br />Brown dwarfs can form in the same way as stars, say astronomers conducting a search for the mysterious objects. The findings may settle a debate about whether brown dwarfs form like stars or are remnants of a violent ejection from a dense cloud of gas. <br /><br />Brown dwarfs have been an enigma ever since they were discovered in the mid-1990s. The dim bodies are too massive to be called planets - about 10 to 75 times the mass of Jupiter - yet not big enough to ignite hydrogen fusion and glow like a star.<br /><br />One early theory suggests brown dwarfs form like stars. But the claim is largely circumstantial, based on the fact that they both appear to have dusty discs surrounding them at birth. An alternative theory proposes that small proto-stars forming in a dense gas cloud are ejected before they are big enough to trigger fusion. <br /><br />Testing these theories is not easy as brown dwarfs are usually very faint, but leftover heat from their birth does allow them to glow for a short while. Using this as a guide to seek out brown dwarfs, Kevin Luhman, from Harvard University, Massachusetts, US, trained the Magellan telescopes at Chile's Las Campanas Observatory on a star cluster 540 light years away in the Chameleon constellation.<br /><br /><br />Free floating <br /><br /><br />He found a dozen new brown dwarfs floating freely, but one pair stood out. "At first I thought the double image was a blur from the telescope but spectroscopy readings confirmed the presence of a binary brown dwarf. It was an accidental find," says Luhman.<br /><br />Calculations showed that the two brown dwarfs were orbiting each other at 240 times the distance between the Earth and Sun, a distance 10 times greater than other brown dwarfs pairs. <br /><br />Since even the slightest tug could upset this fragile balance, Luhman suggests the pair could not have formed
 
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