NASA engineers continued to review data and recover debris from the Space Shuttle Columbia today as the analysis of what caused the orbiter to break up Saturday en route to landing continued.
Space Shuttle Program Manager Ron Dittemore told an afternoon briefing that several teams of engineers are making progress in their study of data and video from Columbia's launch and entry, but cautioned that it is a "massive job" requiring round-the-clock efforts to piece together the events that led to a loss of communications with the Shuttle over north central Texas 16 minutes prior to touchdown.
Still, Dittemore said NASA would pause Tuesday for a memorial ceremony at the Johnson Space Center at 1:00 p.m. EST to honor the lives and the memory of Columbia's astronauts, Rick Husband, William McCool, Dave Brown, Kalpana Chawla, Mike Anderson, Laurel Clark and Ilan Ramon. President and Mrs. Bush will join NASA Administrator Sean O'Keefe at JSC for the memorial which is closed to the public, but which will be broadcast on NASA Television.
Dittemore said the memorial represents an opportunity to take time to remember the sacrifice of the astronauts, to mourn them and to "remember our friends."
Dittemore offered additional and refined information regarding the timeline of events that led to Columbia's breakup on Saturday (all times CST):
- At 7:52 a.m. CST, three-left main gear brake line temperature sensors showed an unusual rise in the left wheel well area.
- At 7:53 a.m., a fourth left brake line strut actuator temperature sensor showed a 30-40 degree rise in temperature over a five-minute period, slightly higher than reported yesterday.
- At 7:55 a.m., A fifth left brake line main gear sensor showed a sharp rise in temperature.
- At 7:57 a.m., left wing temperature sensors failed "off-scale low", meaning no further data was being received on the ground.
- And at 7:59 a.m., just before communications was lost with Columbia, there was evidence of drag on the aerosurfaces of the left wing, causing two out of four yaw steering jets in that area of the Shuttle to fire for 1.5 seconds to counteract the increased drag.
Dittemore said more time will be needed to retrieve an additional 32 seconds of data acquired by ground computers after communications was lost with Columbia to see if it is useful to the inquiry. He said engineers would go directly to the Tracking and Data Relay Satellite System ground station hub in White Sands, New Mexico to collect and analyze that data in its pristine form.
Although the investigative teams have a "high interest" in the left hand wheel well area of Columbia, Dittemore cautioned that a temperature increase there does not indicate that a structural problem occurred as a factor in the vehicle's breakup.. In fact, Dittemore said the data suggests that "something else" may have been happening at the time, not indicative of a structural breach.
Responding to inquiries regarding a piece of foam insulation which fell off Columbia's external fuel tank about 80 seconds after launch that struck the left wing of the Shuttle, Dittemore said imagery analysis showed that the foam measured about 20 inches by 16 inches by 6 inches and weighed about 2.67 pounds. He reiterated that engineering analysis conducted during the flight concluded for NASA managers that although the foam might have caused some structural damage to the wing area, it would not have been sufficient to cause a catastrophic event.
"There is some other missing link contributing to this event," Dittemore said. We are extremely interested in seeing any debris that may have fallen upstream of the main impact area," referring to any additional debris which might be recovered in an area to the west of Texas.
Earlier today, former President George H.W. Bush and Mrs. Barbara Bush visited the International Space Station flight control room at the Johnson Space Center, Houston, TX to pay their respects to the flight controllers and to the Expedition 6 crew aboard the orbital complex.
The former president told Expedition 6 Commander Ken Bowersox, Flight Engineer Nikolai Budarin and NASA ISS Science Officer Don Pettit that President Bush relayed his "full confidence in the space program" in a conversation with the elder Bush Sunday. The former president told the crew the men and women of NASA were showing "great courage" in the wake of the accident.
Bowersox, Budarin and Pettit spent the day preparing for the docking of a Russian Progress resupply vehicle to the ISS Tuesday at 9:50 a.m. EST. The new cargo ship, which contains a ton of food, fuel and supplies for the crew, was successfully launched Sunday from the Baikonur Cosmodrome in Kazakhstan. NASA TV coverage of the Progress docking to the ISS begins at 9 a.m. CST Tuesday.
The next STS-107 Accident Response briefing will be held on Tuesday, Feb. 4 at NASA Headquarters in Washington at 4:30 p.m. EST. Status reports will be issued as developments warrant.
NASA TV is on AMC-2, Transponder 9C, vertical polarization at 85 degrees west longitude, 3880 MHz, with audio at 6.8 MHz.
