Chinese scientists propose new way to reveal first galaxies

This photo taken on May 23, 2023 shows Mount Qomolangma and the galaxy, in southwest China's Tibet Autonomous Region. (Xinhua/Sun Fei)

BEIJING, July 10 (Xinhua) -- Chinese scientists have recently introduced a new method to reveal the nature of the first galaxies and dark matter in the early universe, according to a paper published in the journal Nature Astronomy.

The 21-cm absorption lines (21-cm forest) are the system of narrow absorption lines appearing in the spectra of high redshift background sources due to the intervening neutral hydrogen atoms.

Researchers from the National Astronomical Observatories under the Chinese Academy of Sciences delved into the previously little-discussed 21-cm forest probe and proposed an innovative statistical measurement scheme.

They discovered that by using the one-dimensional power spectrum measurement of the 21-cm forest signal in the cosmic dawn era, the upcoming Square Kilometer Array radio telescope would be able to simultaneously reveal the properties of the universe's first galaxies and dark matter, according to the paper.

The ground-breaking methods are of great significance for unraveling the mystery of dark matter and the formation of celestial bodies in the early universe and will further promote people's understanding of dark matter and shed light on the formation and evolution of the universe's structure, the researchers said.