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 at Sunset
Explanation: Sunsets may be the most watched celestial event, but lately sunsets have even offered something extra . A sunspot so large it was visible to the naked eye is captured in Swiss skies in this sunset scene from January 5, crossing left to right near the center of a solar disk dimmed and distorted by Earth's dense atmosphere. Detailed views reveal a large solar active region composed of sunspots, some larger than planet Earth itself. Cataloged as active region AR 1944, on January 7 it produced a substantial solar flare and a coronal mass ejection (CME) forecast to reach Earth . The CME could trigger geomagnetic storms and aurora on January 9.
| Date | January 8, 2014 |
|---|---|
| Credit | Image Credit & Copyright: Jürg Alean |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |
