The 500 Meter Aperture Spherical Radio Telescope (FAST) in China’s Guizhou province has discovered abundant gas-rich galaxies in the distant Universe.
According to the study, the newly discovered galaxies contain similar or greater amounts of atomic hydrogen gas than previously studied galaxies. These discoveries are considered an important step forward in advancing knowledge about the formation and evolution of galaxies.
Using the 500 Meter Aperture Spherical Radio Telescope (FAST) in Guizhou province in southwestern China, scientists have discovered an abundance of gas-rich galaxies in the distant Universe.
The results of the research were published online Friday in The Astrophysical Journal Letters.
According to the study, the newly discovered galaxies, whose radio wave oscillations took almost as long to reach Earth as the age of the solar system, contain similar or greater amounts of atomic hydrogen gas than tens of thousands of galaxies previously studied with other radio telescopes.
Lead author Xi Hongwei of the National Astronomical Observatory of the Chinese Academy of Sciences (NAOC) and colleagues from Australia, the United States and Russia have uncovered the properties of six new highly redshifted galaxies.
“In the future, a larger sample will allow us to improve our understanding of the formation and evolution of galaxies,” the paper said.
Hydrogen, the most common element in the universe, is abundant in spiral galaxies like the Milky Way Galaxy in its neutral state. Neutral hydrogen is the main component of the cold interstellar medium (ISM) and serves as a fuel reservoir for star formation. However, understanding the evolution of the cold interstellar medium in galaxies is limited by the sensitivity of current radio telescopes.
Peng Bo, a scientist at the Chinese Academy of Sciences, said, “We conducted the Blind Neutral Hydrogen Search or FAST Ultra-Deep Survey. These discoveries are part of ongoing research, demonstrating the extraordinary sensitivity of the world’s largest radio telescope.”
“The new FAST survey has so far discovered more than a hundred new galaxies up to 5 billion light-years away. The discoveries are expected to eventually reach over a thousand.”
The researchers concluded that galaxies 4 billion years ago had much more star-forming gas than today’s galaxies and that distant galaxies have much larger gas reserves than previously believed.
However, because the newly discovered galaxies are very distant, very faint and have different wavelengths, FAST was unable to detect their visual counterparts with the same accuracy as optical telescopes. With the help of experts using the largest optical telescopes in the US and Russia, similar galaxies were finally identified.
Peng said the galaxies in question were found to contain two to three times more stars than the Milky Way but ten times more hydrogen gas mass.
“This successful collaborative program between Chinese and Australian radio astronomers demonstrates the enormous potential of the next generation of radio telescopes,” said Lister Staveley-Smith, a professor at the University of Western Australia.
FAST, the world’s largest single-dish radio telescope, has a reception area equivalent to 30 standard football fields. Located in a deep and round karst depression in Guizhou province, FAST officially began operations in 2020 and officially opened to the world on March 31, 2021.
Source: Xinhua
