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.
Sunspot Region 30
Explanation: The solar active region designated number 10030 (or simply region 30) is now appearing on the visible hemisphere of the closest star . Dwarfed by the Sun's disk, the group of sunspots which make up region 30 actually cover an enormous area -- nearly 10 times the size of Earth. The panels above were recorded July 15, 16, and 17 (top to bottom) by the MDI instrument on the space-based SOHO Observatory as the solar rotation slowly carried the large, dynamic sunspot group across the Sun's nearside . On July 15, a powerful solar flare erupted from this region followed by a coronal mass ejection . The energetic cloud of electrically charged particles swept past our fair planet yesterday, and as a result enhanced auroral activity is possible.
| Date | July 18, 2002 |
|---|---|
| Credit | Credit: MDI , SOHO , ESA , NASA |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |



