STS-93 Day 1 Highlights

On Friday, July 23, 1999, 1:00 a.m. CDT, STS-93 MCC Status Report # 1 reports:

The Space Shuttle Columbia blasted off late Thursday night (early Friday morning, Eastern time) to carry five astronauts to orbit for the long-awaited deployment of Chandra X-Ray Observatory, which will unveil previously invisible mysteries of the universe.

After two previous postponements, Commander Eileen Collins, Pilot Jeff Ashby and Mission Specialists Cady Coleman, Steve Hawley and Michel Tognini lit up the skies at Kennedy Space Center.at 11:31 p.m. Central time Thursday (12:31 a.m. Eastern time Friday), to kick off the 95th mission in shuttle program history. It was the 20th nighttime launch.

About 5 seconds after liftoff, flight controllers noted a voltage drop on one of the shuttle^Òs electrical buses. Because of this voltage drop, one of two redundant main engine controllers on two of the three engines shut down. The redundant controllers on those two engines -- the center and right main engines -- functioned normally, allowing the engines to fully support Columbia^Òs climb to orbit. The left engine was unaffected. Main engine controllers receive commands from the shuttle^Òs general purpose computers, and send commands to main engine components. Flight controllers and the crew continue to work to identify more precisely the cause of the voltage drop.

Less than nine minutes after liftoff, the first female shuttle commander and her crew were in orbit, ready to begin a full night of work to prepare Chandra for its deployment as the third of NASA^Òs Great Observatories. It will study the invisible, and often violent mysteries of x-ray astronomy.

After the astronauts open their cargo bay doors, they will conduct health checks on the Chandra telescope and its two-stage solid-fuel Inertial Upper Stage booster. If all goes as planned, the astronauts will send commands later this morning to elevate the 56-foot long spacecraft to its deployment position behind Columbia^Òs crew cabin. After a critical ^Ógo-no go^Ô decision by flight controllers in Houston and at the Chandra Operations Control Center in Cambridge, Mass., cables routing electrical power to Chandra from Columbia will be disconnected; Chandra will be on internal battery power until its solar arrays are deployed.

The schedule calls for Coleman and Tognini to command Chandra to be spring-ejected from its cradle at 6:48 a.m. Central time. Collins and Ashby then will maneuver Columbia to a ^Ówindow protection^Ô orientation with the belly of the shuttle pointed toward the Inertial Upper Stage booster nozzle. One hour after deployment, with Columbia about 30 nautical miles behind Chandra, the telescope^Òs booster is scheduled to ignite in two stages, sending Chandra to its preliminary elliptical orbit. The telescope eventually will reach an oval orbit one-third of the distance to the Moon to conduct its astronomical observations.

Chandra^Òs solar arrays are to unfurl just prior to the separation of the Inertial Upper Stage^Òs second stage, at which point telescope controllers in Massachusetts will begin several weeks of activation procedures before Chandra officially begins its astronomical investigations.

Columbia^Òs astronauts are in excellent shape, with the shuttle currently orbiting the Earth at an altitude of 178 by 175 miles.

The next STS-93 status report will be issued about 9:30 a.m. Central time after Chandra^Òs Inertial Upper Stage has been jettisoned to complete its work.

On Friday, July 23, 1999, 9:30 a.m. CDT, STS-93 MCC Status Report # 2 reports:

The Chandra X-Ray Observatory is flying free of the Shuttle Columbia following a textbook deployment earlier this morning and the successfully firing of its Inertial Upper Stage booster to place the new telescope on course for an orbit which will take it almost one-third of the way to the moon for its astronomical investigations.

A little more than seven hours after Columbia and its five astronauts were launched from the Kennedy Space Center. Chandra was spring-ejected from a cradle in the shuttle^Òs cargo bay at 6:47 a.m. Central time, as Columbia flew over the Indonesian Island chain. Commander Eileen Collins, the first female Shuttle Commander, maneuvered Columbia to a safe distance away from the telescope as an internal timer counted down to the first of a two-phase ignition of the solid-fuel Inertial Upper Stage.

The IUS lit up as scheduled at 7:47 a.m., and a few minutes later, shut down as planned, sending Chandra on a highly elliptical orbit which will be refined over the next few weeks by a series of firings of telescope thrusters, designed to place Chandra in an orbit about 6900 x 87,000 statute miles above the Earth.

After the IUS^Ò second stage shut down, Chandra^Òs solar arrays deployed at 8:22 a.m. on command from telescope controllers at the Chandra Operations Control Center in Cambridge, Massachusetts, who will oversee the activation of the observatory^Òs systems and its scientific activities. The IUS then separated from Chandra at 8:49 a.m. CDT, establishing it with the Hubble Space Telescope and the Compton Gamma Ray Observatory as the third in a series of four astronomical instruments designed by NASA to paint a comprehensive portrait of the unknown mysteries of the universe.

With Chandra safely on its way and the major objective of their mission successfully completed, the astronauts will end their long day and begin an eight-hour sleep period at 10:31 a.m. Central time. They^Òll be awakened at 6:31 tonight to begin their second day in orbit, a day devoted to secondary experiments in the shuttle^Òs middeck area.

Columbia is flying smoothly on in an orbit 187 x 176 miles above the Earth, circling the planet every 90 minutes with its systems operating in excellent shape.

The next STS-93 status report will be issued at approximately 9:30 a.m. Central time this morning after Chandra^Òs Inertial Upper Stage has been jettisoned to complete its work.

Go to STS-93 Flight Day 2 Highlights: