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new findings by nasa's chandra x-ray

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observatory have provided a major

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advance in understanding a type of

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supernova believed critical to studying

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dark energy

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a zoom into this composite image of the

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andromeda galaxy also known as m31 shows

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astronomers that the merger of what's

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left of two dense stars is the likely

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cause of many type 1a supernovas

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type 1a supernovas have been used to

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measure the accelerated expansion of the

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universe astronomers believe that

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expansions being caused by dark energy

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something they know very little about

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theorizing that this mystery mass energy

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makes up as much as 74 percent of the

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universe

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launched by sts-93 on july 23 1999 the

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chandra x-ray observatory is one of

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nasa's great observatories

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it has obtained unprecedented x-ray

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images of exotic environments that help