|
|
Spacecraft
Locking On and Staying Steady
Sunshade Door
|
Located at the front of the spacecraft where radiation enters
the telescope, the Sunshade door is one of the most basic and
important elements of the spacecraft system. The Sunshade door
remained closed until Chandra achieved pointing control in
orbit. Now that it is opened, it shadows the entrance of the
telescope to allow it to point as close as 45 degrees to the
Sun.
Aspect Camera
|
The pointing control and aspect of determination system has
gyros, an aspect camera, Earth and Sun sensors, and reaction
wheels to monitor and control to very high accuracy where the
telescope is pointing at any given moment. It is as if you could
locate the bulls-eye on a target one kilometer (0.6 miles) away
to the precision of three millimeters--about the size of a
pinhead. This system can also put the Observatory into various
levels of inactive, quiet states known as "safe modes" of
operation during emergencies.
|
