Scientists have detected a faint signal that has been emitted by hydrogen gas in a galaxy which is located more than five billion light years away. This is almost double the previous record. Radio emission from hydrogen in a distant galaxy was observed by the International team of scientists using the Very Large Array of the National Radio Astronomy Observatory in the US. It was then found that billions of young, massive stars surrounded by clouds of hydrogen gas would have been there.
Radio astronomers use hydrogen, the most abundant element in the universe and the raw fuel for creating stars, to detect and understand the makeup of other galaxies.
Radio telescopes, until now, have only been able to detect the emission of hydrogen from relatively nearby galaxies.
In 2014, the previous record was set when the researchers from Swinburne University in Australia detected atomic hydrogen in a galaxy three billion light years from Earth. This was made possible using Arecibo radio telescope in Puerto Rico.
“Due to the upgrade of the Very Large Array, this is the first time we’ve been able to directly measure atomic hydrogen in a galaxy this far from Earth,” said lead author Ximena Fernandez from Rutgers University in the US.
“These signals would have begun their journey before our planet even existed, and after five billion years of travelling through space without hitting anything, they’ve fallen into the telescope and allowed us to see this distant galaxy for the very first time,” said Fernandez.
“A question we hope to answer is whether galaxies in the past had more gas being turned into stars than galaxies today. Our record breaking find is a galaxy with an unusually large amount of hydrogen,” said Fernandez.
This success for the team comes after the first 178 hours of observing time with the Karl G Jansky Very Large Array (VLA) radio telescope for a new survey of the sky called the ‘COSMOS HI Large Extragalactic Survey’, or CHILES.
Once it is completed the CHILES survey will have collected data from more than 1,000 hours of observing time. The study was published in the Astrophysical Journal Letters.
(With inputs from PTI)