Science Instrument Command and Data Handling Unit

Pictured is the Science Instrument Command and Data Handling (SI C&DH) unit that flew on Servicing Mission 4 in 2009, replacing the SI C&DH unit that failed on Hubble in 2008. The failure of the original SI C&DH unit led to Servicing Mission 4 being pushed back from September 2008 to May of 2009.