The Milk Way is spinning about 24 percent slower because of dark matter. This is the first time this slowdown has been definitively measured. Astrophysicists have predicted this slowdown for 30 years.
The study was published in the journal Monthly Notices of the Royal Astronomical Society. The researchers used the Gaia space telescope to make their observations. The researchers looked at the Milky Way’s galactic bar that is made up of billions of stars and trillions of solar masses.
One of the co-author of the paper said, “Astrophysicists have long suspected that the spinning bar at the centre of our galaxy is slowing down, but we have found the first evidence of this happening.”
Tree-ring structure of Galactic bar resonance
Monthly Notices of the Royal Astronomical Society, Volume 505, Issue 2, August 2021, Pages 2412–2426