Galaxy 'Metamorphosis' Since The Big Bang Revealed
Even galaxies transform their structure over their lifetimes, reveal scientists. Scientists who used the Hubble and Herschel telescopes showed how most galaxies underwent 'metamorphosis' since they were formed in the Big Bang, Cardiff University reported.
Researchers hope that their experiments would help them to reveal how the changes happened.
"Many people have claimed before that this metamorphosis has occurred, but by combining Herschel and Hubble, we have for the first time been able to accurately measure the extent of this transformation," said Professor Steve Eales, from Cardiff University's School of Physics and Astronomy.
Studying 10,000 galaxies included in the Herschel ATLAS and GAMA projects, researchers classified the galaxies into two main types: "flat, rotating, disc-shaped" galaxies similar to the Milky Way; and "large, spherical" galaxies containing a high number of disordered stars.
About 83 percent of stars formed since the Big Bang started as disc-shaped, but have now changed to spherical galaxies. Hence, a metamorphosis seems to have occurred, due to a number of catastrophic events, such as two disk-dominated galaxies close to each other till gravity merges them into one, with a major pileup of stars.
Another theory suggests the galaxies merged in a more peaceful manner, with the stars coming together as a disc and moving to the galactic center.
"Galaxies are the basic building blocks of the Universe, so this metamorphosis really does represent one of the most significant changes in its appearance and properties in the last [eight] billion years," Eales concluded, according to hngn.
The findings were published in a recent edition of the Monthly Notices of the Royal Astronomical Society.
