KEY EVIDENCE. “Some of the most straightforward and long standing evidence for DM comes from the rotation curves of spiral galaxies. In a spiral galaxy stars and gas clouds move in circular orbits due to gravity, and their speeds can be measured using the Doppler shift of the Hydrogen 21cm line.” (DM = dark matter).
https://lnkd.in/e6ifiQMn
linkedin post 2022-06-29 05:12:48
Nigel Fleming
September 21, 2022