A long-standing mystery about the Milky Way probably has an answer. Here's what scientists say
Article by: Andacs Robert Eugen, on 01 May 2022, at 09:03 am Los Angeles time
Scientists probably have an answer to a mystery in the center of our galaxy, which has been debated for years. They have not ruled out any hypothesis ranging from dark matter to possible pulsars.
Well, a new study published in the journal Nature might explain the origins of gamma rays at the center of our galaxy.
These gamma rays were first detected in 2009 by the Large Area Telescope, the primary instrument on NASA's Fermi Gamma-ray Space Telescope.
The new study says that those gamma rays are probably produced by millisecond pulsars.
These are the remains of a dead star, which (the pulsars) no longer have fuel, but emit radiation. This may be a plausible explanation for why there are such gamma rays.
"Our work does not throw any doubt on the existence of the signal, but offers another potential source," said Dr. Roland Crocker, an astronomer in the Research School of Astronomy and Astrophysics at the Australian National University.
And these millisecond pulsars rotate a hundred times per second, according to Crocker.
"It is based on millisecond pulsars - neutron stars that spin quickly - around 100 times a second," he said.
Scientists already know that millisecond pulsars emit gamma rays, from past observations of them.
"Scientists have previously detected gamma-ray emissions from individual millisecond pulsars in the neighborhood of the Solar System, so we know these objects emit gamma-rays."
"Our model demonstrates that the integrated emission from a whole population of such stars, around 100,000 in number, would produce a signal entirely compatible with the Galactic Center excess."
"The nature of dark matter is entirely unknown, so any potential clues garner a lot of excitement," Dr. Crocker said.
"But our results point to another important source of gamma-ray production."
The same can be said for the gamma rays observed in the galaxy Andromeda, the closest galaxy to us. Still, millisecond pulsars could be the best explanation.
And depending on the intensity, as well as the length on which these gamma rays were observed, the number of millisecond pulsars in the area can be estimated.
Source: Nature Astronomy