Follow The Spots
Explanation:
The Sun rotates on its axis about once every 27 days.
How can you tell?
Just follow the sunspots.
This composite picture was constructed from solar images recorded
daily by
the MDI instrument on board the space-based
SOlar and Heliospheric Observatory (SOHO).
It shows
the Sun's visible surface for most days of
August 1999 so that the same sunspots appear many times as
the solar rotation carries them across the
face of the Sun.
Sunspot temperatures are around 5,000 degrees C. but the
spots appear dark as they are actually cooler than the surrounding
regions of the solar surface.
The sequential images of the
sunspot groups show how these
regions with high magnetic fields change from day to day.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
