Hubble is scheduled for routine servicing much like your
family car. When you take care of your car with regular maintenance
such as new tires and batteries it will last much longer
and perform better. The same is true of Hubble. But instead
of bringing Hubble to the ground for servicing, astronauts
are trained to make "house calls" hundreds of miles above
the Earth. Astronauts pilot the shuttle to rendezvous with
Hubble, use a robotic arm to place it in the shuttle's cargo
bay, and then install the new equipment. After the work is
complete, the crew sets Hubble free and returns it to service.
This picture shows the start of a servicing mission with the
launch of the space shuttle.