| 
Credit & Copyright: Alan Friedman  
(Averted Imagination)  
  
  
  
Explanation:
Awash in a sea of  
plasma and anchored in  
magnetic  
fields, sunspots are planet-sized,  
dark islands in  
the  
solar photosphere, the bright surface of the Sun.  
  
Dark  
because they are slightly cooler than the surrounding surface,  
this group of sunspots is captured in a close-up  
telescopic snapshot from July 11.  
  
The field of view spans nearly 100,000 miles.  
  
They lie in the center of active region AR1520, now crossing the  
Sun's visible face.  
  
In fact, an  
X-class solar flare and  
coronal mass ejection erupted  
from AR1520 on July 12, releasing some of the energy stored in the  
region's twisted magnetic fields.  
  
Headed this way, the coronal mass ejection is expected to  
arrive today and may trigger  
geomagnetic storms.  
  
As a result, some weekend auroral displays could grace  
planet Earth's skies along with  
Sunday's  
predawn conjunction of bright planets and crescent Moon.  
  
| 
January February March April May June July August September October November December  | 
  | |||||||||||||||||||||||||||||||||||||||||||||||||||||||
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Based on Astronomy Picture
Of the Day
Publications with keywords: active region
Publications with words: active region
See also:

