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On July 23, 1999, house shuttle Columbia took to the skies on its 26th journey into house, to ship its heaviest payload ever – the Chandra X-ray Observatory. The STS-93 crew included Commander Eileen M. Collins, the first woman to command a space shuttle mission, Pilot Jeffrey S. Ashby, and Mission Specialists Catherine “Cady” G. Coleman, Steven A. Hawley, and Michel A. Tognini of the French Area Company (CNES). On the mission’s first day, they deployed Chandra, essentially the most highly effective X-ray telescope. With a deliberate five-year lifetime, Chandra continues its observations after 1 / 4 century. For the subsequent 4 days, the astronauts labored on twenty secondary middeck payloads and carried out Earth observations. The profitable five-day mission ended with an evening touchdown.
Left: The STS-93 crew patch. Center: Official picture of the STS-93 crew of Eileen M. Collins, left, Steven A. Hawley, Jeffrey S. Ashby, Michel A. Tognini of France, and Catherine “Cady” G. Coleman. Proper: The patch for the Chandra X-ray Observatory.
Tognini, chosen by CNES in 1985 and a member of NASA’s class of 1995, acquired the primary task to STS-93 in November 1997. He beforehand flew aboard Mir as a cosmonaut researcher, spending 14 days aboard the station in 1992. On March 5, 1998, First Girl Hilary R. Clinton introduced Collins’ task as the primary lady house shuttle commander in a ceremony on the White Home along with President William J. “Invoice” Clinton. NASA introduced the remainder of the crew the identical day. For Collins, chosen within the class of 1990, STS-93 represented her third house mission, having beforehand served as pilot on STS-63 and STS-84. Ashby, a member of the category of 1994, made his first flight aboard STS-93, whereas Coleman, chosen in 1992, made her second flight, having flown earlier than on STS-73. Hawley made his fifth flight, having beforehand served as a mission specialist on STS-41D, STS-61C, STS-31, and STS-82. He has the excellence of constructing the final flight by any member of his class of 1978, greater than 21 years after his choice.
Left: Schematic of the Chandra X-ray Observatory displaying its main elements. Proper: Diagram of the trajectory Chandra took to realize its closing operational 64-hour orbit across the Earth – IUS refers back to the two burns of the Inertial Higher Stage and IPS to the 5 burns of Chandra’s Integral Propulsion System.
As a result of the Earth’s environment absorbs X-ray radiation emitted by cosmic sources, scientists first got here up with the concept of a space-based X-ray telescope within the Seventies. NASA launched its first X-ray telescope known as Einstein in 1978, however scientists wanted a extra highly effective instrument, and so they proposed the Superior X-ray Astrophysics Facility (AXAF). After a serious redesign of the telescope in 1992, in 1998 NASA renamed AXAF the Chandra X-ray Observatory after Indian American Nobel Prize-winning theoretical physicist Subrahmanyan Chandrasekhar who made important contributions to our data about stars, stellar evolution, and black holes. Chandra, the third of NASA’s 4 Nice Observatories, can detect X-ray sources 100 instances fainter than any earlier X-ray telescope. At 50,162 kilos together with the Inertial Higher Stage (IUS) it used to realize its operational orbit, Chandra stays the heaviest payload ever launched by the house shuttle, and at 57 toes lengthy, it took up almost the whole size of the payload bay. It has far exceeded its anticipated five-year lifetime, nonetheless returning helpful science after 25 years.
Left: The STS-93 crew throughout the Terminal Countdown Demonstration Take a look at. Center: The Chandra X-ray Observatory loaded into Columbia’s payload bay. Proper: Liftoff of Columbia on the STS-93 mission carrying the Chandra X-ray Observatory and the primary lady shuttle commander.
Columbia returned to KSC following its earlier flight, the STS-90 Neurolab mission, in Might 1998. Staff in KSC’s Orbiter Processing Facility (OPF) serviced the orbiter and eliminated the earlier payload. With all 4 orbiters at KSC on the similar time, employees quickly stowed Columbia within the Automobile Meeting Constructing (VAB), returning it to the OPF for closing preflight processing on April 15, 1999. Rollover of Columbia from the OPF to the VAB befell on June 2, the place employees mated it with an exterior tank and two stable rocket boosters. Following built-in testing, the stack rolled out to Launch Pad 39B on June 7. The crew participated within the Terminal Countdown Demonstration Take a look at on June 24. Staff positioned Chandra in Columbia’s payload bay three days later.
On July 23, 1994, Columbia thundered into the evening sky from KSC’s Launch Pad 39B to start the STS-93 mission. Two earlier launch makes an attempt on July 20 and 22 resulted in scrubs as a consequence of a defective sensor and dangerous climate, respectively. As Columbia rose into the sky, for the primary time in shuttle historical past a lady sat within the commander’s seat. Far beneath, issues arose that might have led to a catastrophic abort state of affairs. Through the engine ignition sequence, a gold pin in Columbia’s proper engine got here unfastened, ejected with nice power by the speedy circulate of scorching gases, and struck the engine’s nozzle, punching holes in three of its hydrogen cooling tubes. Though small, the hydrogen leak triggered the engine’s controller to extend the circulate of oxidizer, making the engine run hotter than regular. In the meantime, a short-circuit knocked out the middle engine’s digital management unit (DCU) and the appropriate engine’s backup DCU. Each engines continued powered flight and not using a redundant DCU, with a failure in both inflicting a catastrophic abort. Though this didn’t happen, the upper than anticipated oxidizer utilization led to foremost engine cutoff occurring 1.5 seconds early, leaving Columbia in a decrease than deliberate orbit. The shuttle’s Orbiter Maneuvering System engines made up for the deficit. The harrowing occasions of the powered flight prompted Ascent Flight Director John P. Shannon to remark, “Yikes! We don’t want any extra of those.”
Left: Eileen M. Collins, the primary lady shuttle commander, shortly after reaching orbit. Proper: First time house flyer STS-93 Pilot Jeffrey S. Ashby, shortly after reaching house.
After reaching orbit, the crew opened the payload bay doorways and deployed the shuttle’s radiators, and eliminated their cumbersome launch and entry fits, stowing them for the rest of the flight. The astronauts ready for the mission’s major goal, deployment of Chandra, and in addition started activating a number of the middeck experiments.
Left: The Chandra X-ray Observatory in Columbia’s payload bay shortly after reaching orbit. Center: Chandra raised to the deployment angle. Proper: Chandra departs Columbia.
Coleman had prime duty for deploying Chandra. After preliminary checkout of the telescope by floor groups, the astronauts tilted Chandra and the IUS to an angle of 29 levels. After further checks, they tilted it as much as the discharge angle of 58 levels. Slightly over seven hours after launch, Coleman deployed the Chandra/IUS stack. Collins and Ashby flew Columbia to a secure distance, and about an hour after deployment, the IUS fired its first stage engine for about two minutes, adopted by a two-minute burn of the second stage. This positioned Chandra in a short lived elliptical Earth orbit with a excessive level of 37,200 miles. After separation of the IUS, Chandra used its personal propulsion system over the subsequent 10 days to lift its altitude to six,214 miles by 86,992 miles, its operational orbit, circling the Earth each 64 hours. For the subsequent 4 days of the mission, the astronauts operated about 20 middeck experiments, together with a know-how demonstration of a treadmill vibration isolation system deliberate for the Worldwide Area Station.
Left: Michel A. Tognini works with the Business Generic Bioprocessing Equipment. Center: Jeffrey S. Ashby checks the standing of the Area Tissue Lab experiment. Proper: Catherine G. Coleman harvests vegetation from the Plant Development in Microgravity experiment.
Left: Catherine G. Coleman, left, and Michel A. Tognini pose close to the Light-weight Versatile Photo voltaic Array Hinge know-how demonstration experiment. Center: Stephen A. Hawley checks the standing of the Micro Electromechanical Programs experiment. Proper: Tognini locations samples of the Organic Analysis in Canisters experiment right into a gaseous nitrogen freezer.
Left: Eileen M. Collins runs on the Treadmill Vibration Isolation System. Center: Stephen A. Hawley, left, and Michel A. Tognini function the Southwest Ultraviolet Imaging System instrument. Proper: Inflight {photograph} of the STS-93 crew.
A collection of the STS-93 crew Earth remark images. Left: Laguna Verde in Chile. Center left: Dawn over the Mozambique Channel. Center proper: Darling River and lakes in Australia. Proper: The Society Islands of Bora Bora, Tahaa, and Raiatea.
Left: Eileen M. Collins prepares to carry Columbia residence. Center: Columbia streaks by means of the skies over NASA’s Johnson Area Middle in Houston throughout reentry. Proper: Collins guides Columbia to a easy landing on the Shuttle Touchdown Facility at NASA’s Kennedy Area Middle in Florida.
Left: Three holes seen within the hydrogen cooling tubes of Columbia’s proper foremost engine, seen after touchdown. Center: The STS-93 crew pose in entrance of Columbia on the Shuttle Touchdown Facility at NASA’s Kennedy Area Middle in Florida. Proper: Eileen M. Collins addresses the gang at Houston’s Ellington Area throughout the welcome residence ceremony for the STS-93 crew, as Vice President Albert “Al” A. Gore and different dignitaries pay attention.
On the finish of 5 days, the astronauts completed the final of the experiments and ready for the return to Earth. On July 28, they closed Columbia’s payload bay doorways, donned their launch and entry fits, and strapped themselves into their seats for entry and touchdown. Collins piloted Columbia to a easy touchdown on KSC’s Shuttle Touchdown Facility, finishing the 12th evening touchdown of the shuttle program. The crew had flown 80 orbits across the Earth in 4 days, 22 hours, and 50 minutes. Columbia wouldn’t fly once more till March 2002, the STS-109 Hubble Servicing Mission-3B. A postflight investigation into the reason for the quick on ascent that led to 2 DCUs failing revealed a wire with frayed insulation, probably attributable to employees inadvertently stepping on it, that rubbed towards a burred screw head that had probably been there since Columbia’s manufacture. The incident resulted in important modifications to floor processes throughout shuttle inspections and repairs. With regard to the pin ejected throughout engine ignition that broken the hydrogen cooling tubes, investigators discovered that these pins by no means handed any acceptance testing. Since STS-93 marked the final flight of that era of foremost engines, newer engines integrated a distinct configuration, requiring no design or different modifications.
Benefit from the crew narrate a video concerning the STS-93 mission. Learn Hawley’s recollections of the STS-93 mission in his oral historical past with the JSC History Office.
