Astronomers discover seven new galaxies that seem to appear suddenly

By Shruti Saxena | Last Updated: Nov 20, 2014, 09:58 AM IST
Astronomers discover seven new galaxies that seem to appear suddenly

Zee Media Bureau/Shruti Saxena

New Delhi: Providing a deeper insight into the universe and its galaxies, scientists have discovered seven new galaxies that seemed to be appearing from nowhere, 700 million years after the Big Bang.

A team of astronomers, led by graduate student Akira Konno and Dr Masami Ouchi, used the Subaru Telescope in Japan, to identify to search a particular type called Lyman-alpha Emitters (LAEs) which are low mass galaxies.

Galaxy clusters are the most massive objects in the universe, containing hundreds to thousands of galaxies, bound together by gravity.

The universe was born about 13.8 billion years ago in an event called the Big Bang. At that time, first stars and galaxies were formed and later their ultraviolet light ionised which is a process called 'cosmic reionisation'.

Next, the astronomers searched for early LAE galaxies at a distance of 13.1 billion light years, in a bid to investigate the phenomenon of cosmic reionisation.

Akira Konno was quoted as saying: 'At first we were very disappointed at this small number'.

'But we realised that this indicates LAEs appeared suddenly about 13 billion years ago.

'This is an exciting discovery. We can see that the luminosities suddenly brightened during the 700 to 800 million years after the Big Bang. What would cause this?'

The study is important as it throws light on the concept of cosmic reionisation and the properties of the LAEs in early universe.

The study is published in the Astrophysical Journal.