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Credit & Copyright: Mike Killian /  
AmericaSpace  
  
   
Explanation:
Fixed to a tripod and looking east across the Kennedy Space  
Center's Turn Basin,  
a  
camera captured these star trails  
as a series of short exposures  
over a three hour period on the evening of January 23rd.  
  
Positioned just a few miles from  Space Launch Complex 41 at Cape  
Canaveral Air Force Station, it also captured a spectacular night  
launch of an Atlas V rocket carrying NASA's  
Tracking  
and Data Relay Satellite TDRS-L.  
  
Creating the trails,  
the apparent motion of the stars through the  
sky is just a reflection of the daily rotation of planet Earth on its axis.  
  
But that rotation is also the reason the  
rocket streak  
follows a path arcing east across the Atlantic.  
  
Launching toward  
the east, in the direction of Earth's rotation,  
adds the rotation velocity to the rocket  
and reduces the fuel needed to reach orbit.  
  
A little ironically, TDRS-L is destined for a  
geostationary orbit.  
  
From there, 36,000 kilometers or so above the  
equator, it's orbital period will match Earth's rotation  
and the satellite will hang motionless  
in planet Earth's sky.  
  
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NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Based on Astronomy Picture
Of the Day
Publications with keywords: star trail - launch
Publications with words: star trail - launch
See also:

