Science Instrument Command and Data Handling (SI C&DH) unit works with Hubble's Data Management Unit (DMU) to process, format, and temporarily store information on Hubble's digital recorders or transmit science and engineering data to the ground.
Animation showing the replacement of the Science Instrument Command and Data Handling unit (SI C&DH) during Hubble Space Telescope Servicing Mission 4.
Wide-Field Planetary Camera 2 (WFPC2) was installed in Dec 1993 and used to obtain high resolution images of astronomical objects. This camera was removed in the last servicing mission so it is no longer in service.