Coronal Inflow
Credit & Copyright: N. R. Sheeley, Jr. and Y.-M. Wang
(NRL),
SOHO -
LASCO Consortium,
ESA,
NASA
Explanation:
The active Sun has thrown a lot our way lately, including
storms of particles
streaming outward in the solar wind and
clouds of plasma
which triggered
awesome auroral displays.
Still, a growing body of
intriguing observations
from the LASCO instrument on board the
space-based
SOlar and Heliospheric Observatory
(
SOHO)
indicates material also flows back toward the Sun, starting from
over 2 million kilometers above its
visible surface.
Relatively hard to detect against the outflowing
solar
corona, a dark inflowing cloud's relative motion is tracked
above in two highly processed images recorded an hour apart.
The solar surface, graphically shown by the yellow
quarter circle at the lower right,
is blocked from view by a smooth
occulting disk.
Fighting against a
solar
wind outflow of about 120 kilometers per
second the cloud seems to be moving inward at 50-100 kilometers per
second.
Occasionally
appearing as
often as once per hour,
the clouds, seem to be dragged in by collapsing
magnetic field loops rather than gravity alone.
Researchers are now
working
to relate this surprising inflow to the
solar wind and magnetic
environment
of the Sun.
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.
