Astronomers Detect Hydrogen Radio Emissions Coming From Distant Galaxy

In a major breakthrough, a team of international scientists have detected a faint signal of hydrogen in an extremely distant galaxy which is more than 5 billion light-years away.

The team detected the radio emissions from hydrogen using Karl G. Jansky Very Large Array (VLA) radio telescope of the National Radio Astronomy Observatory in New Mexico, reported SCI News.

 The astronomers found that the galaxy would have contained billions of young, massive stars surrounded by clouds of neutral hydrogen gas.

Radio astronomers use hydrogen, which is considered as the most abundant element in the universe and is also the raw fuel for creating stars, to detect and understand the composition of other galaxies.

"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, Dr Ximena Fernandez from Rutgers, the State University of New Jersey, according to Science Alert.

"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," he added.

This marks the first time that hydrogen signals have been detected from such a distant galaxy, almost double the previous record. It was back in 2014 when Swinburne University astronomers used the Arecibo radio telescope in Puerto Rico to detect atomic hydrogen in a galaxy about 3 billion light-years away. Until now, radio telescopes have only been able to detect the emission signature of hydrogen from relatively nearby galaxies.

"This is precisely the goal of the project, to study how gas in galaxies has changed through history," Fernández said, according to HNGN.

"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."

The team used the VLA radio telescope in order to collect data for the COSMOS HI Large Extragalactic Survey (CHILES), collecting data from more than 1,000 hours of observing time.

The team members including Dr Attila Popping from International Centre for Radio Astronomy Research and the ARC Centre of All-sky Astrophysics (CAASTRO) in Australia are currently working with Amazon Web Services to process and move the large volumes of data via the "cloud".

"For this project we took tens of terabytes of data from the Very Large Array, and then processed it using Amazon's cloud-based servers to create an enormous image cube, ready for our team to analyse and explore," said Popping.

The study findings have been published in the Astrophysical Journal Letters.