APOD
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.
Dusting Spiral Galaxies
Explanation: How much dust is in spiral galaxies? Does it block out much of the starlight? Because astronomers rely on an accurate knowledge of galaxy properties to investigate a wide range of problems, like galaxy and quasar evolution and the nature of dark matter , answers to simple questions like this are key. This striking, detailed Hubble Space Telescope image of dust in the outer reaches of a foreground spiral galaxy (left) back lit by an elliptical galaxy offers an elegant approach to providing the answers . As expected, dust lanes in the foreground galaxy seem to be associated with spiral arms. But surprisingly , many dust regions are not completely opaque and the dust is more smoothly distributed than anticipated . This “overlapping” pair of galaxies is cataloged as AM1316-241 and is about 400 million light-years away in the constellation Hydra .
| Date | January 16, 1998 |
|---|---|
| Credit | Credit: W. Keel and R. White (U. Alabama), NASA |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |