A radio telescope detects thousands of galaxies in early space

The images capture dramas billions of years ago in the early universe – glowing galaxies, bright stars exploding into supernovae, and blazing jets fired from black holes.

European giant radio telescope LOFAR has discovered stars born in tens of thousands of distant galaxies with unprecedented precision, in a series of studies released Wednesday.

Using techniques that correspond to very long exposures and with a field of view approximately 300 times larger than a full moon, scientists have been able to distinguish galaxies like the Milky Way deep in the ancient universe.

“The light of these galaxies travels billions of years to reach Earth; that means we see galaxies as they were billions of years ago, when they formed most of their stars, ”said Philip Best of the British University of Edinburgh, who led a detailed study of the telescope in a press release.

The LOFAR telescope combines signals from a vast network of more than 70,000 individual antennas in countries from Ireland to Poland, connected by a high-speed optical network.

They are able to observe very weak and low-energy light, invisible to the human eye, created by ultra-energy particles that travel close to the speed of light.

The researchers said this allows them to study supernova star explosions, clusters of galaxy clusters and active black holes, which accelerate these particles in bumps or jets.

By observing the same celestial regions over and over again and arranging the data to create one very long exposure image, the scientists were able to detect the radio brightness of the exploding stars.

The most distant objects discovered were from the time when the Universe was only a billion years old. It is now about 13.8 billion years old.

“When a galaxy forms stars, a lot of stars explode at the same time, which accelerates very high energy particles and galaxies begin to radiate,” said Cyril Tasse, an astronomer at the Paris Observatory and one of the study’s authors, published in a series of papers in Astronomy & Astrophysics.

About 3 billion years after the Big Bang, he said “it’s really fireworks” in young galaxies, with “the peak of star formation and black hole activity.”

The telescope focused on a wide area of ​​the northern hemisphere sky, with the equivalent of an exposure time 10 times longer than that used in the creation of its first space map in 2019.

“This gives much finer results, like a photograph taken in the dark with the exposure of as many things as you can tell for as long as possible,” Tasse told AFP.

Depth images are created by combining signals from thousands of telescope antennas, including more than four petabytes of raw data – equivalent to about a million DVDs.