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.

February 12, 1997
See Explanation.  Clicking on the picture will download 
 the highest resolution version available.

Comet Hale-Bopp Develops a Tail
Credit and Copyright: P. H. Mikuz and B. Dintinjana (Crni Vrh Obs.,U. Ljubljana)

Explanation: Comet Hale-Bopp has quite a tail to tell already. This remarkable comet was first discovered in 1995, even before Comet Hyakutake. Since then, this erupting snowball continues to fall into our inner Solar System and is starting to put on quite a show. Comets have been known throughout history to show tails that spread across the sky. In the above picture, the blue stream is the ion tail which consists of ions pushed away from the comet's head by the solar wind. The ion tail always points directly away from the Sun. Comet Hale-Bopp is now visible in the morning sky, moving a few degrees each day. Comet Hale-Bopp is expected to be at its best and brightest in late March and early April.

Tomorrow's picture: More Jets from Comet Hale-Bopp


< Archive | Index | Search | 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.