China’s FAST telescope finds biggest atomic cloud ever discovered

Name: Nasa offers deepest-ever look in space, the farthest humanity has ever seen in time and distance
Uploaded: 2022-10-19T15:00:13.000Z
Duration: 1 min 28 s
Description: Nasa offers deepest-ever look in space, the farthest humanity has ever seen in time and distance

Colossal cloud is 20 times larger than the Milky Way galaxy and probably a billion years old

The finding could help scientists understand the origins of galaxies and reveal similar gaseous structures lurking elsewhere in the universe

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Scientists discovered a mammoth space cloud by pointing an ultra-powerful radio telescope towards Stephan’s Quintet, a well-known grouping of galaxies. Photo: Handout

Ling Xinin Beijing

Published: 11:00pm, 19 Oct 2022Updated: 11:25pm, 19 Oct 2022

An international team led by Chinese scientists has discovered the biggest atomic cloud in the universe – a surprising finding that could help researchers better understand the origins of galaxies.

The cloud, made up of hydrogen atoms, measures about 2 million light years across and is 20 times larger than our Milky Way galaxy, according to a paper published in the journal Nature on Wednesday. One light year is about 9.46 trillion km (5.88 trillion miles).

The discovery was only possible with the help of an ultra-powerful telescope in southwestern China’s Guizhou province. Astronomers from China, Europe and the United States found the cloud after they pointed the Five-hundred-metre Aperture Spherical radio Telescope (FAST) – the world’s largest single-dish radio telescope – in the direction of a group of galaxies known as Stephan’s Quintet.

“Since its discovery 145 years ago, Stephan’s Quintet has been extensively studied by various ground-based and space telescopes,” said lead author Xu Cong from the National Astronomical Observatories under the Chinese Academy of Sciences in Beijing.

High-powered telescopes have captured stunning views of Stephan’s Quintet. For example, Nasa’s James Webb Space Telescope has caught one of the galaxies colliding with another at high speed, which generated a massive shock wave.

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Nasa offers deepest-ever look in space, the farthest humanity has ever seen in time and distance

Xu’s team wanted to use the unparalleled sensitivity of FAST to better understand how the galaxies interacted with one another when they first came together as a group.

To do this, they looked for hydrogen atoms in the area around Stephan’s Quintet. The atoms give off a unique “signature” emission that can reveal information about events that happened long ago.