Астронет: Астрономическая картинка дня Спиральные вихри на планете Земля http://variable-stars.ru/db/msg/1163556/eng |
Credit & Copyright: STS 41G Crew,
NASA
Explanation:
Can you identify this
stellar nebula?
How many
light-years from Earth did you say?
Looking like
a twisting cloud
of gas and dust between the stars
this wispy nebulosity is actually close by - a spiral eddy
formed near the North Atlantic Gulf Stream off the East coast of the US.
Tens of miles across,
spiral eddies are an ocean current phenomenon
discovered by
observations from manned spacecraft.
Imaged by the
Challenger space shuttle crew
during the STS 41G mission
this eddy is dramatically visible due to the low sun angle
and strong reflection of sunlight.
The reflection is caused
by a very thin biologically produced
oily film on the surface of the swirling water.
Prior to STS 41G these eddies were thought to be rare but are now
understood to be a significant dynamic feature of ocean currents.
However, no good explanation of their origin or persistence exists.
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.