The Mysterious Force Killing Off Galaxies – Is Earth and the Milky Way Next?

A MYSTERIOUS force is wiping out galaxies across the universe baffling scientists who are desperately trying to figure out what is killing off the stars.
Fresh research by boffins at the International Centre for Radio Astronomy Research (ICRAR) may have finally found the answer to the phenomenon. 

The study of 11,000 galaxies showed their gas – the lifeblood of galaxies – was being stripped away on a massive scale throughout the local universe. 

The process, called ‘ram-pressure stripping’, means galaxies cannot form new stars, sending them into an early death spiral. 

Elusive dark matter, while invisible, makes up 27 per cent of our universe, with ordinary matter accounting for just five per cent with the remaining 68 per cent consisting of dark energy. 


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Galaxies are embedded within dark matter clouds, which are referred to as dark matter halos.

Galaxies are embedded within dark matter clouds, which are referred to as dark matter halos. 

Toby Brown, leader of the study, said: “During their lifetimes, galaxies can inhabit halos of different sizes, ranging from masses typical of our own Milky Way to halos thousands of times more massive.

“As galaxies fall through these larger halos, the superheated intergalactic plasma between them removes their gas in a fast-acting process called ram-pressure stripping.


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The study of 11,000 galaxies showed their gas – the lifeblood of galaxies – was being stripped away

“You can think of it like a giant cosmic broom that comes through and physically sweeps the gas from the galaxies.”

The absence of gas means the galaxies cannot form new stars, slowly killing them as their existing stars die off.

Mr Brown continued: “It dictates the life of the galaxy because the existing stars will cool off and grow old.

“If you remove the fuel for star formation then you effectively kill the galaxy and turn it into a dead object.”


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The process, called ‘ram-pressure stripping’, means galaxies cannot form new stars.

The main process which stars run out of gas is called strangulation, but Mr Brown noted the key differences between then and ram-pressure stripping. 

He said: “Strangulation occurs when the gas is consumed to make stars faster than it’s being replenished, so the galaxy starves to death.


 earth space galaxy death universe GETTY

Elusive dark matter, while invisible, makes up 27 per cent of our universe

“It’s a slow-acting process. On the contrary, what ram-pressure stripping does is bop the galaxy on the head and remove its gas very quickly – of the order of tens of millions of years – and astronomically speaking that’s very fast.”

Published in the journal Monthly Notices of the Royal Astronomical Society, co-author Dr Barbara Catinella said the team combined the largest optical galaxy surgery and the largest set of radio observations for atomic gas in galaxies to discover what was killing off the galaxies.