Conventional wisdom among astrophysicists dictates that galaxies don’t start out with much dark matter, the unseen material that seems to make up most of the mass in the universe. Instead, they speculate, galaxies pick up dark matter over time through some unknown process.
But new observations from the McDonald Observatory in Texas have found a striking counterexample: an ancient galaxy loaded with dark matter.
The research, published Wednesday in The Astrophysical Journal, describes DSFG850.95, a galaxy 9 billion light-years away. That means the light that reaches Earth from this galaxy is 9 billion years old — providing a peek into the universe’s distant past.
But unlike other ancient galaxies, DSFG850.95 is chock-full of dark matter, according to the McDonald observations.