Servicing Mission 4 (SM4)

Also known as STS-125, Servicing Mission 4 (SM4) was the final servicing mission for the Hubble Space Telescope and prioritized installing new instruments and improving systems to prolong Hubble’s lifespan.

Major highlights from the mission include the installation of the Cosmic Origins Spectrograph (COS) and the Wide Field Camera 3 (WFC3) to replace the Space Telescope Imaging Spectrograph (STIS) and the Wide Field Planetary Camera 2 (WFPC2). Crew members also replaced battery unit modules and gyroscope rate sensing units, and made other observatory system repairs to improve Hubble’s performance.

SM4 Crew Members:

Scott Altman, Mission Commander

Gregory Johnson, Pilot

Michael Good, Mission Specialist

Megan McArthur, Mission Specialist

Andrew Feustel, Mission Specialist

Michael Massimino, Mission Specialist

John Grunsfeld, Mission Specialist

Learn more about SM4 at NASA's website: https://science.nasa.gov/mission/hubble/observatory/missions-to-hubble/servicing-mission-4/