It’s a galaxy far, far away… The opening of Star Wars has never stuck as well as for SDSSJ0826+5630, a galaxy recently discovered by astronomers located nearly 9 billion light-years away.
It’s a feat that scientists and astronomers have achieved: spotting a radio signal from a galaxy 8.8 billion light-years from Earth, the greatest distance ever captured for such a signal. with current tools. The search, led by a team of Canadian and Indian scientists supervised by McGill University, unearthed SDSSJ0826+5630, an impossible name for this star cluster (the galaxy in question is probably made up of black holes).
A galaxy really far away
To pick up this signal, the astronomers used the Giant Metrewave Radio Telescope, a radio telescope installed in Pune, India. The radio signal in question emits on the spectral line at 21 cm, an emission of wavelength equal to 21 cm in vacuum. The electromagnetic radiation at this length is the result of large clouds of atomic hydrogen.
« A galaxy emits different types of radio signals “, explains Arnab Chakraborty, researcher at McGill University. ” Until now, it was only possible to pick up this particular signal from a nearby galaxy, which limited our knowledge to the galaxies closest to Earth. “. This discovery obviously pushes the known limits: “ This will help us understand the composition of galaxies located very far from Earth “, he adds.
Our own solar system began to exist about 4.55 billion years ago. SDSSJ0826+5630 could therefore help us unravel the mysteries of star formation in extremely distant galaxies, which in turn will give us clues to the creation of our own universe. More pragmatically, this discovery opens new opportunities to probe the cosmic evolution of stars and galaxies with existing low-frequency radio telescopes.