Star Clouds in the Andromeda Galaxy
January 28, 1999
Low Res. (158 KB)
High Res. (688 KB)
Object Name: Part of Andromeda Galaxy (M31)
Telescope: Subaru Telescope / Cassegrain Focus
Filter: R (red)
Date: UT 1999 Jan 13
Exposure: 900 sec
Field of View: 3 acmin by 4 arcmin
Orientation: North is upper-right, east is upper-left
Position: RA(J2000.0)=0h40m33.51s, DEC(J2000.0)=+40d44m45s
The Andromeda galaxy (Messier 31) is an assembly of some 100 billions of stars and is a spiral galaxy similar to our own Galaxy. It is located 2.5 million light years away, and is one of our nearest neighbors. This image, taken with a red filter, shows just a tiny part (corresponding to the white rectangle in the attached sheet) of the Andromeda galaxy, whose total apparent size is about 3 degrees. The image shows many points of light which are individual stars in the Andromeda galaxy, and appears very like our own Milky Way galaxy when observed with a small telescope. It is difficult to resolve each of these stars from the ground, but the high angular resolution and sensitivity of the Subaru Telescope enables us to resolve these stars with one short exposure. The bright region from the lower-left to upper-right is part of the spiral structure, wheremany young stars are shining brightly.
This image was taken with a large optical camera called Suprime-Cam, which is equipped with six 2048x4096 CCDs specially tuned for astronomical observations. Vertical and horizontal black stripes are gaps between the CCD chips and faulty pixels. Many such exposures, taken with the telescope pointing slightly changed, can be combined to remove these features and produce beautiful images.