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.
Anticrepuscular Rays Over Florida
Explanation: What's happening over the horizon? Although the scene may appear somehow supernatural , nothing more unusual is occurring than a setting Sun and some well placed clouds. Strangely, the actual sunset was occurring in the opposite direction from where the camera was pointing. Pictured above are anticrepuscular rays . To understand them, start by picturing common crepuscular rays that are seen any time that sunlight pours though scattered clouds. Now although sunlight indeed travels along straight lines , the projections of these lines onto the spherical sky are great circles . Therefore, the crepuscular rays from a setting (or rising) sun will appear to re-converge on the other side of the sky. At the anti-solar point 180 degrees around from the Sun , they are referred to as anticrepuscular rays . While enjoying the sunset after visiting NASA's Kennedy Space Center in Florida , the photographer chanced to find that an even more spectacular sight was occurring in the other direction just over the Atlantic Ocean -- a particularly vivid set of anticrepuscular rays .
| Date | September 17, 2006 |
|---|---|
| Credit | Credit & Copyright: Daniel Herron |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |



