Mars Odyssey 2001 Schedule of Events for Orbital Insertion
October 23, 2001 All times are EDT, All events in Earth Recieved
Time (Times in parentheses are UTC, October 24) 7:56 p.m. About
two-and-a-half hours before the engine firing, commands are sent
to fire small onboard thrusters to "desaturate" or unload the
momentum of the spinning reaction wheels. These devices are
similar to gyroscopes and are used to control the spacecraft's
orientation - its positioning in three axes - so that it is
facing the desired direction. The desaturation readies the
reaction wheels for the task of turning Odyssey into the proper
pointing position for the orbit insertion engine firing. 10:06
p.m. Catalyst bed heaters, called "catbed" heaters, are turned
on to warm (02:06) the "catbeds" to an operational temperature
for more efficient operation of the reaction control thrusters.
These small jets control the spacecraft's position in three
axes: pitch, yaw and roll. They will fire intermittently during
the main engine firing to