00:01Visit Chandra's Beautiful Universe
00:063C297
00:09A distant and lonely galaxy
00:11appears to have pulled in and assimilated all of its former
00:15companion galaxies. This result, made with NASA's
00:19Chandra X-ray Observatory and the International Gemini Observatory
00:23may push the limits for how quickly astronomers expect galaxies to grow
00:27in the early universe. The unexpectedly solo galaxy
00:32is located about 9.2 billion light-years from
00:35Earth and contains a quasar, a supermassive black hole
00:39pulling in gas at the center of the galaxy and driving powerful jets
00:43of matter seen in radio waves. The environment of this
00:47galaxy, known as 3C297, appears to
00:51have the key features of a galaxy cluster, enormous structures
00:55that usually contain hundreds or even thousands of galaxies.
00:59Yet 3C297
01:01stands alone. A team of
01:03researchers expected to see at least a
01:05dozen galaxies within 3C297,
01:08yet they found only one.
01:10Accurate distance
01:11measurements from Gemini data
01:13revealed that none of the 19 galaxies
01:15that appear close to 3C297 in the optical image
01:19are actually at the same distance as the lonely galaxy.
01:23The question is, what happened to all of these galaxies in 3C297?
01:27The team thinks the gravitational pull of the one large galaxy
01:31combined with interactions between the galaxies
01:34was too strong and they merged with the large galaxy.
01:37For these galaxies, apparently resistance was futile.
01:42The researchers think 3C297 is no longer a galaxy cluster, but a fossil group.
01:48This is the end stage of a galaxy pulling in and merging with several other galaxies.
01:54While many other fossil groups have been detected before,
01:57this one is particularly distant,
02:00at 9.2 billion light-years away.
02:03The previous record holders for fossil groups
02:05were at distances of 4.9
02:07and 7.9 billion light-years.
02:10It may be challenging
02:11to explain how the universe can create
02:13this system only 4.6 billion
02:15years after the Big Bang.
02:17This result doesn't break the current
02:19ideas of cosmology,
02:21but it begins to push the limits on how
02:23quickly both galaxies and
02:25galaxy clusters must have formed.
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