The age of the universe is approximately 13.2 billion years and its consisting galaxies are also estimated at almost the same age, however the shape of these galaxies and distant from each other is not constant, it keeps on changing, says a new study.
In the report submitted in The Monthly Notices of the Royal Astronomical Society, the team of astronomers discovered that a significant number of galaxies have gone through a major change in shape or ‘metamorphosis’ since their inception out of the Big Bang. The team then classified the galaxies into two main types: flat, rotating, disc-shaped galaxies and large oval-shaped galaxies with disordered stars.
The outcome points at an enormous transformation by which disc-shaped galaxies turned to oval-shaped galaxies. “Essentially, we measured the total energy output of all the galaxies in a small region of the sky, out in space and therefore back in time, and found that most of the energy output was from disk galaxies.” said a researcher.
The team of researchers found out that 83 percent of stars were once grouped in slowly rotating disc-shaped galaxies, whereas now, less than 50 percent of stars inhabit flat disc-shaped galaxies. From round disc-shaped galaxies to oval ones, many galaxies have gone a massive transformation over the past 8 billion years according the report submitted by researchers.
Lead author Professor Steve Eales told the two main possible causes for this metamorphosis:“(a) galaxy mergers in which two disk galaxies are scrambled together into a elliptical; or (b) the gradual motion of newly formed stars in a disk into the center of a galaxy, gradually building up a big pile of stars.” He added that the cause may be “something we haven’t thought of.”
To arrive at the conclusion, a team of astronomers from Cardiff College peered into the far-away galaxies using the Hubble and Herschel telescopes.
Mathew Allen, a PhD scholar at Cardiff University and a member of the staff, said “This can be a big step in understanding how the galactic inhabitants has advanced over billions of years.”
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