STS-93

STS-93.

STS-93 was a Space Shuttle mission conducted by NASA in July 1999 that deployed the Chandra X-ray Observatory into Low Earth orbit before transfer to a highly elliptical orbit via the Inertial Upper Stage. The flight involved a crew drawn from USNA and USAF backgrounds, included a historic female commander, and required a scrubbed launch attempt and in-flight troubleshooting that drew on expertise from Marshall Space Flight Center, Johnson Space Center, and contractors such as Lockheed Martin and TRW Inc..

Mission overview

The mission objective was to deliver the Chandra X-ray Observatory—a flagship-class Great Observatories project developed by NASA, the Smithsonian Astrophysical Observatory, and the Harvard College Observatory—into proper orbit for X-ray astronomy operations. Secondary objectives included on-orbit verification of the shuttle's payload bay systems and testing procedures involving the Remote Manipulator System operated from the Mission Control Center at Johnson Space Center. After deployment, the observatory was scheduled for orbit-raising using the two-stage Inertial Upper Stage built by Lockheed Martin and fueled and integrated with support from Kennedy Space Center and Cape Canaveral Air Force Station personnel. The mission also served as an operational demonstration of procedures developed following investigations at White House-level reviews and internal assessments after prior shuttle anomalies.

Crew and payload

The four-person crew consisted of a commander and three mission specialists drawn from United States Navy and United States Air Force officers and civilian astronaut corps at NASA Ames Research Center and Johnson Space Center. The commander was a pioneering woman with prior experience in Space Shuttle Columbia operations and naval aviation; other crew members included personnel with backgrounds in Hubble Space Telescope servicing mission planning, Orbital Sciences Corporation payload integration, and extravehicular activity support. The primary payload, the Chandra X-ray Observatory, incorporated instrumentation developed by the Smithsonian Astrophysical Observatory, the Massachusetts Institute of Technology, and partners including Ball Aerospace and Raytheon. Chandra carried the Advanced CCD Imaging Spectrometer and the High Resolution Mirror Assembly, with contributions from institutions such as Harvard-Smithsonian teams and international collaborators from European Space Agency-affiliated groups. Additional cargo included experiments supported by Marshall Space Flight Center and technology demonstrators from Jet Propulsion Laboratory contractors.

Launch and ascent

Launch operations were conducted from Kennedy Space Center Launch Complex 39B following an initial scrub that involved coordination between Mission Control Center flight controllers and engineers from Rockwell International heritage teams. The countdown incorporated holds and troubleshooting with the Space Shuttle Main Engine systems and an auxiliary power unit inspection informed by lessons from earlier flights overseen by the Office of Safety and Mission Assurance. Liftoff placed Space Shuttle Columbia on a trajectory to achieve insertion into a low-inclination orbit; ascent profiles referenced guidance from Johnson Space Center flight dynamics officers, with telemetry relayed through Ground Network stations and the Tracking and Data Relay Satellite System managed by NASA Goddard Space Flight Center. Stage separation, main engine cutoff, and external tank separation proceeded under procedures developed alongside contractors such as Boeing and United Space Alliance.

On-orbit operations

Once in orbit, the crew operated the Canadarm/Remote Manipulator System to grapple and release the Chandra X-ray Observatory for deployment. The deployment sequence required coordination with Inertial Upper Stage teams and onboard navigation guidance systems calibrated by Johnson Space Center specialists. Post-deployment checkout included activation of the observatory's thermal protection and instrument booms, with telemetry downlinked to the Goddard Space Flight Center and processed by the Chandra X-ray Center. Crew activities also featured payload bay equipment inspections, stowage operations involving hardware from Marshall Space Flight Center, and contingencies rehearsed with support from Mission Control Center flight controllers. The mission crew communicated with scientists at institutions such as Harvard College Observatory and Smithsonian Astrophysical Observatory to verify instrument health and begin initial commissioning sequences.

Landing and post-mission analysis

After mission objectives were complete, reentry preparations were coordinated by Mission Control Center and Johnson Space Center flight controllers using guidance from aerodynamic teams that included consultants from Langley Research Center and contractor analysts at Boeing. The shuttle executed deorbit burn and atmospheric reentry procedures leading to a landing on the runway at Kennedy Space Center with post-landing safing and vehicle processing coordinated by United Space Alliance recovery crews. Post-mission analysis involved data handover to the Chandra X-ray Center, engineering assessments at Marshall Space Flight Center, anomaly reviews by the Office of Safety and Mission Assurance, and scientific commissioning performed by teams at the Harvard-Smithsonian Center for Astrophysics. The successful deployment enabled Chandra to begin a decades-long program of X-ray astronomy that produced observations used by researchers at institutions including California Institute of Technology, Massachusetts Institute of Technology, Princeton University, and international partners from European Southern Observatory collaborations.

Category:Space Shuttle missions