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The CrewCargoTimelineEVAShuttle ArchivesPrevious mission: STS-96Next mission: STS-103STS-93: Deployment of the Chandra X-Ray Observatory
Mission Patch
IMAGE: STS-93 Insignia
Mission Highlights
Mission:Chandra X-Ray Observatory Deployment
Launch:July 22, 1999 - 11:31 p.m. CDT
Window:116 Minutes
Landing:July 27, 1999 - 10:20 pm CDT
Duration:4 days, 22 hours, 50 minutes
Related Links
*Chandra Status Report Index
*Hydrogen Leak Photos
*STS-93 Videos
IMAGE: STS-93 crew
The STS-93 astronauts -- in front, Commander Eileen Collins (left) and Mission Specialist Michel Tognini; in back, Mission Specialist Steve Hawley (left), Pilot Jeff Ashby (middle) and Mission Specialist Cady Coleman -- pose for the traditional inflight crew portrait on Columbia's middeck. Click here to see more STS-93 images in the Gallery.

STS-93 Deploys Chandra X-Ray Observatory
Space Shuttle Columbia lifted off for its 26th flight -- mission STS-93 -- on July 22, 1999, at 11:31 p.m. CDT (0431 GMT July 23, 1999). The purpose of the five-day mission was to deploy the Chandra X-Ray Observatory.

However, when Columbia reached orbit, it was 11 kilometers (7 miles) short of its target. This was due to premature main engine cutoff an instant before the scheduled cutoff. This problem was traced to a hydrogen leak in the No. 3 main engine nozzle. The leak was caused when a liquid oxygen post pin came out of the main injector during main engine ignition, striking the hotwall of the nozzle and rupturing three liquid hydrogen coolant tubes. Columbia eventually reached its proper altitude and continued its mission.

On Flight Day 1, the shuttle crew successfully deployed Chandra. The observatory was propelled into orbit by a two-stage Inertial Upper Stage, or IUS. Following the second IUS burn, Chandra's solar arrays were deployed and the IUS separated from the observatory as planned.

During the rest of the mission the crew activated secondary payloads and experiments, including the Southwest Ultraviolet Imaging System which was used to capture ultraviolet imagery of Earth, the Moon, Mercury, Venus and Jupiter.

The astronauts monitored several plant growth experiments and collected data from a biological cell culture experiment. They used the exercise treadmill and the Treadmill Vibration Information System to measure vibrations and changes in microgravity levels caused by on-orbit workouts. High-Definition Television equipment was tested for future use on both the shuttle and the International Space Station to conform to evolving broadcasting industry standards for television products.

IMAGE: Chandra X-Ray Observatory in Space Shuttle Columbia's Payload Bay
*STS-93 Press Kit
*Chandra X-Ray Observatory News

Eileen Collins
IMAGE: STS-93 Commander Eileen Collins
STS-93 Commander Eileen Collins, the first woman to command a shuttle crew, floats on Columbia's middeck during a free moment.

Collins Becomes First Female Shuttle Commander
With the launch of STS-93 on July 22, 1999, Col. Eileen Collins became the first woman to command a space shuttle mission.

Collins became an astronaut in July 1991. Her first space flight was in February 1995 as pilot of STS-63. Her participation in this mission to rendezvous Space Shuttle Discovery with the Russian Space Station Mir made her the first woman to pilot a space shuttle. She also served as pilot on STS-84 in May 1997. This shuttle mission was the sixth to dock with Mir. Collins and her fellow crewmembers conducted several experiments and transferred nearly 3.6 metric tons (4 tons) of supplies and experiment equipment between Space Shuttle Atlantis and the Russian space station.

Curator: Kim Dismukes | Responsible NASA Official: John Ira Petty | Updated: 11/21/2005
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