NASA Astronomy Picture of the Day Collection

Spiral Eddies On Planet Earth

Can you identify this wispy stellar nebula [ http://antwrp.gsfc.…]? How many light-years from Earth [ http://antwrp.gsfc.…] did you say? Resembling a twisting cloud [ http://antwrp.gsfc.…] of gas and dust between the stars this swirling form is actually close by - a spiral eddy formed near the North Atlantic Gulf Stream off the East coast of the U. S. Tens of miles across, spiral eddies are an ocean current phenomenon [ http://daac.gsfc.na…shuttle_oceanography _web/oss_134.html ] discovered by observations from manned spacecraft [ http://daac.gsfc.na…shuttle_oceanography _web/oss_cover.html ]. Imaged by [ http://images.jsc.n…html/10044055.htm ] the Challenger [ http://www.ksc.nasa…] space shuttle crew during the STS 41G [ http://www.ksc.nasa…mission-41-g.html#hi ghlights ] mission this eddie is dramatically visible [ http://daac.gsfc.na…shuttle_oceanography _web/oss_170.html ] due to the low sun angle and strong reflection of sunlight. The reflection is caused by a very thin biologically produced [ http://daac.gsfc.na…OB_main.html ] 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.

STS 41G Crew [ http://www.ksc.nasa…], NASA [ http://www.nasa.gov/]

earth

ocean

spiral eddy

Goddard Space Flight Center (GSFC)

Washington, D.C.

Johnson Space Center (JSC)

Earth

Sun

Challenger

Space Shuttle Orbiter

STS-41G

http://antwrp.gsfc.…

SPD-APOD-ap990116