The Milky Way May Be 50 Percent Bigger Than Previously Thought

astroengine writes: A ring-like filament of stars wrapping around the Milky Way may actually belong to the galaxy itself, rippling above and below the relatively flat galactic plane. If so, that would expand the size of the known galaxy by 50 percent and raise intriguing questions about what caused the waves of stars. Scientists used data collected by the Sloan Digital Sky Survey to reanalyze the brightness and distance of stars at the edge of the galaxy. They found that the fringe of the disk is puckered into ridges and grooves of stars, like corrugated cardboard. "It looks to me like maybe these patterns are following the spiral structure of the Milky Way, so they may be related," said astronomer Heidi Newberg. In other Milky Way new, a Cambridge team has found nine new dwarf satellites orbiting our galaxy. Some of them are definitely dwarf galaxies, and the others may be the same, or globular clusters.

Comments

Re:In which way is it "bigger?"

[Baloroth]

Volume. Well, maybe area, TFA isn't terribly clear (or possibly even radius, now I read it again. Size could refer any of the three. Pretty sure they mean radius, though, now I look at it closer). Not mass, though, that'd be a hell of a lot of extra mass. Basically, the problem is there is a ring of stars around the outer edge of the Milky Way. Astronomers aren't entirely sure where it comes from: if it originated from the Milky Way, and therefore is part of our galaxy properly speaking, or if it's the remnants of a dwarf galaxy that was scattered when it ran into us, or came from some other source. That would tell us a bit more about galaxy formation (or raise more questions about formation, which is almost the same thing).