Nothing lasts an eternity in this Universe, not even a majestic spiral galaxy full of billions of stars. Compared to other cosmic structures, galaxies die in a little peculiar way. A galaxy is considered dead when it cannot give birth to stars anymore.
CNN writes that for the first time ever, astronomers were lucky to witness a remote galaxy as it’s starting to die in a potential major breakthrough. The galaxy in question is ID2299, and what is believed to cause it to die is a cataclysmic cosmic event: a merger with another galaxy.
The galaxy ejects half of the gas it uses for creating stars
The galaxy loses about 10,000 Suns-worth of gas each year. However, ID2299 still has plenty of years to live if it still exists in the present. The galaxy will likely take several tens of million years to die, as it’s located 9 billion light-years away from Earth. This means that astronomers are seeing ID2299 as it was 9 billion years ago. Annagrazia Puglisi, the lead author of the study, declared:
This is the first time we have observed a typical massive star-forming galaxy in the distant Universe about to ‘die’ because of a massive cold gas ejection.
Emanuele Daddi, a study co-author and astronomer at Saclay, declared:
Our study suggests that gas ejections can be produced by mergers and that winds and tidal tails can appear very similar,
This might lead us to revise our understanding of how galaxies ‘die.’
The astronomers captured the images using the imposing ALMA telescope (Atacama Large Milimeter/submilimeter Array) from Chile.
The study was led by Annagrazia Puglisi, a postdoctoral research associate from Durham University in the UK and the Saclay Nuclear Research Centre in France. The findings were published in the journal Nature Astronomy.