Launch from Cape Canaveral (KSC); landing at Cape Canaveral (KSC). The launch was scrubbed on February 21, 2002 and on February 28, 2002 due to technical problems. This flight was the fourth Hubble Space Telescope Servicing mission.

The first EVA by John Grunsfeld and Richard Linnehan occured on March 04, 2002 (7h 1m) to install a new generation solar array on the starboard side of the HST.

The second EVA was performed by James Newman and Michael Massimino on March 05, 2002 (7h 16m) to install the new port-side array and replace one of the four Reaction Wheel Assemblies.

The third EVA by John Grunsfeld and Richard Linnehan was conducted on March 06, 2002 (6h 48m) to exchange the Power Control Unit (PCU), the "electrical heart" of the HST.

The fourth EVA by James Newman and Michael Massimino was performed on March 07, 2002 (7h 18m) to change the Faint Object Camera (FOC) with the Advanced Camera for Surveys (ACS) and to install a new electronic support module für the NICMOS Cryo Cooler.

The fifth and final EVA by John Grunsfeld and Richard Linnehan occured on March 08, 2002 (7h 20m) to install the experimental cooling system (Cryo Cooler), replace the solid nitrogen cooler of NICMOS. It was a new record for the most EVA hours in a single shuttle flight.