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.

2001 November 21
See Explanation.  Clicking on the picture will download
 the highest resolution version available.

The Galactic Ring of NGC 6782
Credit: Rogier Windhorst (ASU) et al., Hubble Heritage Team, NASA

Explanation: Do spiral galaxies look the same in every color? NGC 6782 demonstrates colorfully that they do not. In visible light, NGC 6782 appears to be a normal spiral galaxy with a bright bar across its center. In ultraviolet light, however, the central region blossoms into a spectacular and complex structure highlighted by a circumnuclear ring, as shown in the above representative color Hubble Space Telescope image. Many of the young stars that formed in a recent burst of star formation emit the ultraviolet light. Astronomers are studying possible relationships between the central bar and the ring. Light we see today from NGC 6782 left about 180 million years ago, while dinosaurs roamed the Earth. The galaxy spans about 80,000 light-years and can be seen with a telescope toward the constellation of Pavo.

Tomorrow's picture: 70 kilometers per second

< | Archive | Index | Search | Calendar | Glossary | Education | About APOD | >

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.