China’s FAST Telescope Unveils Abundance of Distant Gas-Rich Galaxies
Astronomers using the Five-hundred-meter Aperture Spherical Radio Telescope (FAST) in southwest China’s Guizhou Province have made a groundbreaking discovery of numerous gas-rich galaxies in the distant universe. The findings, published recently in The Astrophysical Journal Letters, reveal galaxies whose radio wave emissions have traveled nearly the age of the solar system to reach Earth.
These newly discovered galaxies contain similar or even greater amounts of atomic hydrogen gas compared to tens of thousands of galaxies previously surveyed with other radio telescopes. Atomic hydrogen is the most common element in the universe and serves as the primary fuel for star formation within galaxies.
“This new sample provides an opportunity to better investigate the evolution of cool gas in galaxies,” said Xi Hongwei, the lead author from the National Astronomical Observatories under the Chinese Academy of Sciences (NAOC). “A larger sample size in the future will allow us to refine our knowledge of the formation and evolution of galaxies.”
The research team, which includes members from Australia, the United States, and Russia, unveiled the properties of six new high-redshift galaxies. These discoveries are part of the ongoing FAST Ultra-Deep Survey, which aims to explore the distant universe with unprecedented sensitivity.
Peng Bo, a scientist at the NAOC, highlighted the significance of the telescope’s capabilities. “We have carried out a blind neutral hydrogen search. These discoveries show the tremendous sensitivity of the world’s largest radio telescope,” he said. “The new FAST survey has so far discovered over 100 new galaxies at distances of up to 5 billion light-years, with the final number expected to reach over 1,000.”
Neutral hydrogen is abundant in spiral galaxies like the Milky Way and is a key component of the cool interstellar medium—the reservoir of gas that fuels star formation. Understanding the distribution and evolution of neutral hydrogen in galaxies is crucial for unraveling the mysteries of galaxy formation and evolution. However, due to the limitations of existing radio telescopes, our understanding has been limited until now.
The FAST telescope’s superior sensitivity allows astronomers to detect faint radio signals from distant galaxies, providing new insights into the early universe. This discovery marks a significant step forward in astrophysics, offering potential breakthroughs in our comprehension of how galaxies form and evolve over cosmic time.
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China's FAST telescope finds an abundance of distant gas-rich galaxies
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