more Iridium information
MALEY, PAUL D. (paul.d.maley1@jsc.nasa.gov)
Fri, 26 Sep 1997 11:51:17 -0500
I have learned today that there are indeed only 3 main mission antennas.
One points directly forward into the velocity vector with no offset.
But the other two are apparently not aligned 90 degrees on both sides.
Instead, that alignment is 120 degrees. This may explain the 30 degree
offset. The solar arrays articulate depending upon the Beta angle. When
this angle is 0-40 degrees both arrays point exactly at the sun; between
Beta of 40-60 degrees, they are locked at 40 degrees and rotate around
the surface of a cone. Above 60 degree Beta they are locked (no
articulation) so that one points forward and the other points aft. Maybe
Rob can utilize this new data in his prediction model.
Paul D. Maley
DO5/Cargo Operations
NASA Johnson Space Center
Houston TX 77058 USA
phone: 281-244-0208
fax: 281-244-7622
email: paul.d.maley1@jsc.nasa.gov
latitude 29.5378 north; longitude 95.0868 west; altitude 6 m