Mystery at heart of Milky Way galaxy linked to new type of dark matter

March 12, 2025

Evrim Yazgin
Cosmos science journalist




Unexplained chemical reactions observed at the centre of the Milky Way galaxy could be caused by the existence of a type of dark matter not accounted for in current physics.

Milky way stars galaxy space
Credit: sarawut / Moment / Getty Images Plus.

“At the centre of our galaxy sit huge clouds of positively charged hydrogen, a mystery to scientists for decades because normally the gas is neutral,” says Shyam Balaji from King’s College London and one of the lead authors of a new paper published in the Physical Review Letters.

“So, what is supplying enough energy to knock the negatively charged electrons out of them?”

Astronomers have called this area of ionised hydrogen gas clouds the Central Molecular Zone (CMZ).

“The energy signatures radiating from this part of our galaxy suggest that there is a constant, roiling source of energy doing just that, and our data says it might come from a much lighter form of dark matter than current models consider,” Balaji says.

Previous attempts to explain the ionisation relied on cosmic rays – ultrafast and energetic particles. But the energy signatures observed in the CMZ don’t aren’t large enough to be attributed to cosmic rays.

More:
https://cosmosmagazine.com/space/astrophysics/milky-way-galaxy-centre-dark-matter/