the successful Servicing Mission 3A, Hubble is
refreshed and back to work producing amazing science
images. There are two more scheduled servicings
in Hubble's future, Servicing Mission 3B in 2001;
and Servicing Mission 4 in 2003.
Mission 3B will focus on the installation of the
Advanced Camera for Surveys and more efficient,
rigid solar arrays. Astronauts also will install
the aft shroud cooling system, which will allow
the science instruments to operate simultaneously
at lower temperatures. In addition, an advanced
cooling system will be installed on the Near Infrared
Camera and Multi-Object Spectrometer, which became
dormant after its solid nitrogen coolant was exhausted
in January 1999. The application of new external
thermal coverings will be completed.
Mission 4 will see the addition of two new science
instruments, the Cosmic Origins Spectrograph and
the Wide Field Camera 3. A refurbished Fine Guidance
Sensor also will be installed, completing the
refurbishment of all Fine Guidance Sensors on
is scheduled to be decommissioned in 2010.