Scientists weigh Milky Way galaxy

LONDON (AFP) ― The Milky Way galaxy is lighter than previously thought, according to new research published by British-based scientists on Wednesday.

The study led by the University of Edinburgh is the first time that scientists have been able to measure accurately the mass of the galaxy that contains our solar system, the researchers said.

The Milky Way was found to contain only half the mass of its neighbor Andromeda, which has a similar spiral structure to our own.

“We always suspected that Andromeda is more massive than the Milky Way, but weighing both galaxies simultaneously proved to be extremely challenging,” said Dr. Jorge Penarrubia, who led the study.

The research concluded that the extra mass of the Andromeda galaxy was down to dark matter, a little-understood invisible substance that accounts for most of the outer regions of galaxies.

The scientists estimate that the Milky Way contains approximately half as much dark matter as its neighboring galaxy, though the two are of similar dimensions.

The Milky Way and Andromeda are the two largest in a region of galaxies known to astronomers as the Local Group.