Twin stars observed in the Orion Nebula. At this distance the twin stars appear as a single point of light.
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Image Courtesy of NASA-JPL/HST and David James (Vanderbilt)

Newly Born Twin Stars are Far From Identical
News story originally written on June 18, 2008

Astronomers have always thought that twin stars, which are stars that have the same mass and orbit around each other, are identical. So they were surprised when they discovered that twin stars in the Orion Nebula were not identical at all. These stars actually have major differences in their brightness, surface temperature, and possibly even their size.

The newly formed twin stars are about 1 million years old. Since their full life span is about 50 billion years, they are equal to one-day-old human babies.

"The easiest way to explain the observed differences is if one star was fully formed about 500,000 years before its twin. That would be equivalent to a human birth-order difference of about half a day," said Keivan Stassun, one of the scientists who worked on this project.

Last modified July 31, 2008 by Becca Hatheway.

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