Space & Astronomy

Scientists solve mystery of the universe's elusive 'missing matter'

By T.K. Randall
April 15, 2025 ·  1 comment

Where is the missing matter ? Image Credit: ESA / NASA The 'missing matter' or 'missing baryon' problem, which actually has nothing at all to do with dark energy or dark matter, concerns the fact that the amount of ordinary matter (that which makes up stars, planets, asteroids etc.) accounted for by observations and measurements of the cosmos in modern times is only around half that of the amount that we would expect to see based on the amount that was present shortly after the Big Bang.

This discrepancy has long left scientists scratching their heads - where could this missing matter be ?

One long-standing theory is that the missing matter has ended up in extremely low-density clouds of ionized gas stretching large distances out from the center of galaxies, but it has been difficult to definitively confirm whether or not this is actually the case.

Now, though, a new study by a team of 75 scientists has determined that this theory is most likely to be correct.Thanks to new measurements, the researchers were able to discover gas situated five times further away from the center of galaxies than previously thought possible.

Across such an immense volume of space, the collective mass of even a very low-density gas quickly adds up.

"We think that, once we go further away from the galaxy, we recover all of the missing gas," said Dr Boryana Hadzhiyska of UC Berkeley.

That said, more work will be needed to ensure that this really does account for all the missing matter.

"To be more accurate, we have to do a careful analysis with simulations, which we haven't done," said Dr Hadzhiyska. "We want to do a careful job."

Source: IFL Science | Comments (1)

Tags: Matter, Universe