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“Red and Dead” Future for Gas-Guzzling Galaxy

A study of carbon monoxide levels in a galaxy more than 12 billion light years from Earth has revealed that it is running out of gas and headed for a “red and dead” future. The galaxy ALESS65 was first observed in 2011 and is one of less than 20 known distant galaxies to contain carbon monoxide.

Dr Minh Huynh from The University of Western Australia node of the International Centre for Radio Astronomy Research (ICRAR) led the team on their search for galactic carbon monoxide in work published in the Monthly Notices of the Royal Astronomical Society.

“We’re familiar with carbon monoxide here on Earth as the deadly gas that can cause suffocation, but in galaxies it plays an important role in the life cycle of stars,” Huynh said. “Out of the galaxies that we know contain carbon monoxide, less than 20 are as far away from Earth as ALESS65. Out of the billions of galaxies out there, the detections are very rare.”

Huynh said that astronomers hadn’t believed there could be massive “red and dead” galaxies in the distant Universe, so studying galaxies heading towards that fate is important to solve the puzzle of their existence.

Using the Australia Telescope Compact Array radio telescope, the ICRAR team worked out how much carbon monoxide they could see in ALESS65 and extrapolated that to determine how much gas the galaxy has left. “All galaxies have a certain amount of fuel to make new stars,” said Huynh.

“Our galaxy, the Milky Way, has about five billion years before it runs out of fuel and becomes ‘red and dead’, but ALESS65 is a gas guzzler and only has tens of millions of years left – very fast in astronomical terms.”

The team will now turn their attention to the search for carbon monoxide in another galaxy near ALESS65 called ALESS61.