Attention is focused on the left wing because sensors there either failed or measured some unusual conditions of heat, indicating something was happening that wasn't normal.
While plenty of theories about damaged heat protection tiles or wing structure continue to be discussed, Dittemore continued to emphasize Friday that nothing had been ruled out yet, including the possibility that insulating foam falling from the external tank damaged the shuttle's tiles.
As for the image, Dittemore had little to offer in the way of explanation.
"We have looked at it and it's not tremendously revealing to us yet," Dittemore said, noting that photo experts will be called in to examine it. "It's not clear to me there's something there yet. If you're eye is sharp, maybe you can draw a conclusion. I can't."
Dittemore also reported that there are now 350 reports of debris located on the ground in California, Arizona and New Mexico -- although none of those have been confirmed as being Columbia debris.
Still to come
Looking ahead, Congress is expected to begin hearings Wednesday into the Feb. 1 accident in which Columbia and seven astronauts were lost over the skies of Texas.
While many questions remain about how the tragedy occurred, lawmakers are also expected to seek assurances from NASA that the investigation will be thorough and that the work of the independent Columbia Accident Investigation Board (AIB) will be free of any space agency influence or bias. Retired Navy Admiral Harold W. Gehman, Jr, is leading the inquiry.
NASA Administrator Sean O'Keefe promised as much during Thursday's briefing to news media.
"We want the facts and the evidence to speak to the conclusions, ultimately inform the conclusions in terms of what caused this horrific event. And in doing so, we do not want to rule out any theory, any approach, any possible set of factors that could be, when combined, lead to some other judgment. That is a determination that the Columbia Accident Investigation Board will render," O'Keefe said.
To help ensure that independence, deemed critical for NASA's future credibility, the accident board's charter was re-written and its board executive staff loaded with non-NASA support personnel.
Those actions were the direct result of a letter members of Congress sent President George W. Bush on Thursday to encourage him to appoint an investigation board, much like President Reagan did in 1986, when he formed the Rogers Commission to look into the Challenger disaster. In addition to identifying the technical flaw that doomed the shuttle, the Rogers group also found fault with the underlying management structure and decision-making process within the space agency.
"While we commend the openness with which NASA has shared information on the Columbia accident with the public and the Congress, we are concerned that the AIB has the appearance of a non-independent board controlled by NASA," wrote U.S. Rep. Ralph M. Hall (D-Texas) and U.S. Rep. Bart Gordon (D-Tenn.).
"This is not meant in any way to demean the dedication and excellence of NASA's workforce, but to ensure, as President Reagan did 17 years ago, that the AIB would proceed in as unfettered and open a manner as possible," the congressmen wrote.
Who's who
AIB members include Rear Adm. Stephen Turcotte, commander of the Naval Safety Center; Maj. Gen. John Barry, director of plans and programs at Air Force Materiel Command headquarters; Maj. Gen. Kenneth W. Hess, commander of the headquarters for the Air Force Chief of Safety; James N. Hallock, chief of the aviation safety division for the Dept. of Transportation; Steven B. Wallace, director of accident investigation for the Federal Aviation Administration; Brig. Gen. Duane Deal, commander of the Air Force's 21st Space Wing and Scott Hubbard, director of NASA's Ames Research Center.
NASA investigators will continue to look into the disaster and report their findings to the AIB, which will be solely responsible for determining the cause of the accident and identifying the corrective measures required.
"We want the facts and the evidence to speak to the conclusions, ultimately inform the conclusions in terms of what caused this horrific event. And in doing so, we do not want to rule out any theory, any approach, any possible set of factors that could be, when combined, lead to some other judgment. That is a determination that the Columbia Accident Investigation Board will render," O'Keefe said.
Dittemore on Thursday also pledged support to the AIB, saying the NASA teams will do everything they can to assist the board in finding their answers.
"I'm very pleased to have Admiral Gehman here with his team, and we offer our full support. Anything that Admiral Gehman needs, we will provide to him. And we pledge to him that we will continue to support him as we have done in the past. As we have prepared investigation plans and procedures, we will transition our thoughts and our plans over to the board and we'll follow his leadership," Dittemore said.
Debris update
Meanwhile the pieces that will help the AIB solve the puzzle about why Columbia and its crew were lost are expected to be on their way to the Kennedy Space Center in Florida this week.
As of Friday more than 1,000 pieces of shuttle debris had been recovered over an area that encompasses at least four states, with the potential still remaining that fragments of Columbia might be found west of Texas and provide key clues as to the series of events that led to the break up of the vehicle.
Attention is still focused on Columbia's left wing. It was there that a variety of telemetry gave indications of thermal events and structural problems beginning at least eight minutes before all contact was lost at 9 a.m. EST (1400 GMT), Feb. 1.
Many theories have been raised about what happened and why, but as of Friday managers had ruled nothing out -- including the possibility that insulating foam falling from the external tank some 80 seconds after launch set up the series of events that might have triggered the disaster during re-entry. Other news reports suggest that images showing some kind of electrical discharge on Columbia or missing structure from Columbia's left wing could be something to consider.
NASA is using a fault tree analysis to determine every possible failure scenario and then prove or disprove that possibility.
"We have not ruled out any possible cause. And even though we scratch our heads from time to time and wonder if we're going down a right path, it's important to understand that the first step in any investigation is to develop a fault tree," Dittemore said Thursday.
"And in the fault tree, you examine and identify every possible cause no matter how remote or no matter what you think about the possibility of that cause. And once you develop that tree, then you establish a process where you systematically close out each branch of the tree. So in the end, you have left no stone untourched. You have looked at each branch, each possible block, each possible cause and satisfied yourself that you have done a thorough and complete job, independent of what you might think of the probabilities or possibilities," Dittemore said.
Final data
A New Mexico tracking station that recorded the final seconds of the space shuttle Columbia has only 1 second of data that wasn't recorded elsewhere, but it could be a very important second, the station's director said Friday.
NASA's Tracking and Data Relay Satellite System, at the edge of the White Sands Missile Range in southern New Mexico, was collecting information from Columbia as it re-entered Earth's atmosphere last week and disintegrated.
"We were tracking simultaneously from two satellites, one looking at the front (of the shuttle) and the other looking at the back," said James Gavura, station director.
"Both signals were lost at the same time, and then there was 31 seconds (of silence) and then 1 more second of data," he said.
That second could contain information on the position of the shuttle just before it began to tumble and break up, he said.
Although that second hasn't been verified as shuttle data, Gavura said it appears to have the proper signature.
Gavura said the data would be relayed electronically to the Johnson Space Center in Houston, where engineers would analyze it. It comes from a 5-minute period during shuttle re-entry when harsh conditions, including intense heat, tend to garble the signals.
The tracking station uses satellites that can follow shuttles from their orbits all the way to the landing strip.
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