Sydney, November 26 (ANI): Australian astronomers have discovered that the universe is peppered with tiny blue dwarf galaxies known as 'blue fuzzies'.
These tiny galaxies are made up mostly of young hot stars that shine brightly, dominating the light from the galaxies they are in.
According to a report in ABC News, Dr Sarah Brough of the Anglo-Australian Observatory made the discovery while examining data from a study called the Galaxy and Mass Assembly survey (GAMA).
Brough said that the aim of the GAMA survey is to "map out the galatic structure in our local universe, several of magnitude better than previous surveys."
The survey incorporates data from the Sloan Digital Sky Survey, which contains more than 930 thousand galaxies and 120 thousand quasars, and extends to approximately 2.5 billion light years from Earth.
Brough discovered the blue fuzzies while looking at a unique set of spectra.
"When you're doing a survey, one of the most interesting things are the extremes," said Brough. "So, I pulled out the smallest mass objects, about 100 or so, and looked at the Sloan Digital Sky Survey to see what they were," she added.
When she focused on one of the blue fuzzies imaged by the survey, she was surprised to discover that it was in fact an entire galaxy.
Since that first discovery, Brough and her colleagues have examined about a hundred more blue fuzzies.
The discovery suggests that the nearby universe is not dominated by big larger galaxies such as the Milky Way or Andromeda, but by lots of tiny little ones.
Each blue fuzzy is about the same size as the Small Magellanic Cloud, averaging around seven thousand light years across and containing as much mass as seven billion Suns.
According to Brough, blue fuzzies are old galaxies, but unlike Milky Way-sized galaxies that form stars very rapidly, the blue fuzzies have their stars forming at a slow but steady pace, giving them a frosting of young hot stars.
She said that these galaxies are scattered fairly evenly throughout the universe at distances ranging out to seven hundred million light years.
While their distribution follows the voids and filaments which make up the structure of the cosmos, Brough said that they seem to be more common in less dense areas, away from the large galaxies and galaxy clusters.
She believes they've maintained a slow and steady rate of star formation because there are no external forces impacting on them. (ANI)
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