Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

September 8, 1995

The Milky Way's Centre
Credit: NASA, COsmic Background Explorer (COBE) Project

Explanation: NASA's COBE satellite scanned the heavens at infrared wavelengths in 1990 and produced this premier view of the central region of our own Milky Way Galaxy. The Milky Way is a typical spiral galaxy with a central bulge and extended disk of stars. However, gas and dust within the disk obscure visible wavelengths of light effectively preventing clear observations of the centre. Since infrared wavelengths, are less affected by the obscuring material, the Diffuse InfraRed Background Experiment (DIRBE) on board COBE was able to detected infrared light from stars surrounding the galactic centre and produce this image. Of course, the edge on perspective represents the view from the vicinity of our Sun, a star located in the disk about 30,000 light years out from the centre. The DIRBE experiment used equipment cooled by a tub of liquid helium to detect the infrared light which, composed of wavelengths longer than red light, is invisible to the human eye.

Tomorrow's picture: The Last Moon Shot

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/ GSFC
&: Michigan Tech. U.