Stellar Motions of Halo Stars in Milky Way

This illustration shows the disc of our Milky Way galaxy, surrounded by a faint, extended halo of old stars. Astronomers using the Hubble Space Telescope to observe the nearby Andromeda galaxy serendipitously identified a dozen foreground stars in the Milky Way halo. They measured the first sideways motions (represented by the arrows) for such distant halo stars. The motions indicate the possible presence of a shell in the halo, which may have formed from the accretion of a dwarf galaxy. This observation supports the view that the Milky Way has undergone continuing growth and evolution over its lifetime by consuming smaller galaxies.

Credit:

NASA, ESA, and A. Feild (STScI)

About the Image

NASA press release
NASA caption
Id:opo1307a
Type:Artwork
Release date:22 February 2013, 11:16
Size:2400 x 1800 px

About the Object

Type:Milky Way
Category:Illustrations

Image Formats

Large JPEG
880.3 KB
Screensize JPEG
137.0 KB

Zoomable


Also see our


Accelerated by CDN77