Astronomers saw a distant galaxy die for the first time
When the stars in a galaxy stop forming, that galaxy will die. Astronomers, for the first time, observed this phenomenon in a distant galaxy.
According to a CNN report, scientists using the large millimeter / submillimeter array of Atacama telescopes in Chile, were able to capture a “rare sighting” of a galaxy “because it ejected nearly half the gas it uses to form stars.” .
It took nearly nine billion years for light from this galaxy, known as ID2299, to reach Earth, CNN reported – which basically means that astronomers “observe how it came to be when the universe was only 4.5 billion years old (it is now estimated to be 14 billion years old)”.
Galaxy ID2299 is losing the fuel it needs to form stars – 10,000 suns of gas per year – and has so far removed 46% of the galaxy’s total cold gas, the report Explain.
However, at a “rate which is hundreds of times faster than our own Milky Way”, ID2299 is still rapidly forming stars, the report Noted.
The formation of these stars will deplete the rest of the gas in the galaxy and effectively cause “the death of ID2299 in a few tens of millions of years”, the report Explain.
CNN quoted Annagrazia Puglisi, senior researcher and postdoctoral research associate at Durham University in the UK and Saclay Nuclear Research Center in France, who said in a statement: “This is the first time that we are observing a typical massive star-forming galaxy in the distant Universe on the verge of “dying” from a massive ejection of cold gas. “
What could have caused the disappearance of the galaxy?
According to report, the cause of the death of this galaxy, could have been a collision with another galaxy, “which eventually merged to create ID2299.”
Is there convincing evidence that the loss of gas may have been the result of a collision? According to CNN report, the to study says there is – and it’s called a tidal tail – “a long stream of gas and stars stretching out into space after two galaxies come together in a collision.”
Although these tidal tails are generally “too weak” to be seen in galaxies this distance, the to study noted that in this case, the glowing tail was visible to astronomers as it stretched out into space, CNN reported.
Astronomers may need to reconsider previous theories.
Previously, scientists believed that the “end of star formation” occurred when “the winds created by star formation, combined with active black holes in the center of giant galaxies, sent the necessary material to the star formation in space “. CNN cited.
However, the to study noted that if the loss of gas from this galaxy was caused by a merger, “astronomers may have to reconsider the theories about the end of star formation in galaxies.”
CNN quoted Emanuele Daddi, study co-author and astronomer at the Saclay Nuclear Research Center in France, who said: “Our study suggests that gas ejections can be produced by mergers and that winds and tails tidal waves can look very similar. He added: “It might cause us to rethink our understanding of how galaxies ‘die’.”
This sighting was an unexpected discovery.
An interesting aspect of this discovery is that “it was made while astronomers were working on another study of cold gas in distant galaxies,” and although their sighting of ID2299 only lasted a few minutes, “c ‘was enough to capture the tidal tail., ” CNN reported. And, the possibility remains that more could be revealed about the galaxy’s gas ejection, thanks to future observations.
CNN quoted Chiara Circosta, co-author of the study and researcher at University College London, who said in a statement: “ALMA shed new light on the mechanisms that can stop star formation in galaxies distant. Witnessing such a massive disturbance event adds an important piece to the complex puzzle of the evolution of the galaxy. “