DECLINE IN STAR FORMATION ACTIVITY

DECLINE IN STAR FORMATION ACTIVITY

Subject : Science & tech

Context : Recently, a team of astronomers from the National Centre for Radio Astrophysics (NCRA-TIFR) in Pune, and the Raman Research Institute (RRI) have discovered the reason behind decline in star formation activity 8 billion years ago

Concept :

• The study stated that the fuel critical to hydrogen formation is atomic hydrogen gas content of galaxies.
• The researchers used the Giant Metrewave Radio Telescope (GMRT) to measure the atomic hydrogen gas content of galaxies 9 billion years ago.
• The measurement of the atomic hydrogen gas mass was done by using the GMRT to search for a spectral line in atomic hydrogen, which can only be detected with radio telescopes.
• The star formation in early galaxies was so intense that they would consume their atomic gas in just two billion years and if the galaxies could not acquire more gas, their star formation activity would decline and finally cease.
• It appears likely that the cause of the declining star- formation in the Universe is simply that galaxies were not able to replenish their gas reservoirs after some epoch.

About Giant Metrewave Radio Telescope (GMRT)

• It is a unique facility for radio astronomical research using the metre wavelengths range of the radio spectrum.
• It is located at a site about 80 km north of Pune.
• It consists of 30 fully steerable gigantic parabolic dishes of 45m diameter each spread over distances of upto 25 km.
• It has been set up by National Centre for Radio Astrophysics (NCRA), a center of the school of natural sciences of the TIFR.