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 Seething
Explanation: Our Sun's surface is continually changing. This time-lapse movie shows in five seconds what happens in 20 minutes on the Sun's surface near a sunspot . Visible is boiling granulation outside the sunspot, inward motion of bright grains in the outer penumbral region toward the sunspot , and the churning of small magnetic elements between solar granules . Sunspots themselves are relatively cool regions of the solar surface depressed by magnetic fields . The dark lanes surrounding the sunspot are called penumbral filaments, and recent computer simulations have shown that their behavior is also dominated by magnetic fields . The above sequence was taken with the new Dutch Open Telescope last September and focused on a sunspot that measured about 25,000 kilometers across.
| Date | February 23, 2000 |
|---|---|
| Credit | Credit: Peter Sütterlin , DOT Team , SIU |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |



