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Nasa baffled { February 6 2003 } Original Source Link: (May no longer be active)
http://sfgate.com/cgi-bin/article.cgi?f=/c/a/2003/02/06/DEBRIS.TMPhttp://sfgate.com/cgi-bin/article.cgi?f=/c/a/2003/02/06/DEBRIS.TMP
NASA chases debris reports
Agency still baffled by cause of shuttle's catastrophic re-entry
Carl T. Hall, Chronicle Science Writer
Thursday, February 6, 2003
©2003 San Francisco Chronicle | Feedback
URL: http://sfgate.com/cgi-bin/article.cgi?f=/c/a/2003/02/06/DEBRIS.TMP
NASA intensified its search Wednesday for any pieces of the space shuttle Columbia that may have landed in California, saying that may turn up critical clues explaining the orbiter's mysterious breakup over Texas.
A team of six NASA investigators, joined by hazardous-materials experts from the U.S. Environmental Protection Agency, spent the day chasing tips from the public of suspected debris finds, focusing on locations in the South Bay and in Southern California. Two NASA specialists were dispatched to Phoenix to inspect materials in Arizona.
By late Wednesday, however, no confirmed shuttle pieces had been found. Meanwhile, officials at the Johnson Space Center in Texas said they remain mystified as to what could have brought the Columbia down Saturday as it re-entered the atmosphere after an uneventful 16-day mission.
Suspicions focused from the outset on a piece of insulating foam that broke off the shuttle's external fuel tank during lift-off in Florida and struck the Columbia's left wing, perhaps damaging some of the shuttle's heat-shielding tiles.
But shuttle program manager Ron Dittemore insisted that the insulation was too light to have caused damage sufficient to create a "safety of flight issue."
"We believe there's something else," Dittemore said during a news briefing Wednesday. "We're investigating every area. Right now it just does not make sense to us that a piece of (foam) debris could be the root cause for the loss of Columbia and its crew. There has got to be another reason."
'CRITICALLY IMPORTANT' SEARCH
Earlier, Michael Kostelnik, a shuttle manager at NASA in Washington, D.C., said the search for evidence west of the main debris field in Texas and Louisiana was "critically important."
"We're thinking they could be parts of a wing," he said, referring to the materials found on the ground so far in California.
NASA officials were using all the tools they could muster to hone the search, even checking seismic readings taken during the shuttle's final moments.
The Columbia's re-entry sent acoustic waves toward the Earth that were recorded by 150 seismographs from the coast to the Nevada border, said Catherine Puckett, a spokeswoman for the U.S. Geological Survey in Eureka. The shuttle sent acoustic waves from Gualala (Mendocino County) to Markleeville (Alpine County) in a 100-mile-wide swath, she said.
David Oppenheimer, a USGS scientist, said the agency is comparing seismic recordings of the Columbia's flyover with shock waves generated by previous shuttle flyovers to see if any differences might help explain the accident.
There's also a chance that a large piece of debris might have created some discernable vibrations when it hit the ground after plummeting 220,000 feet. Nor is seismic data the only way to track any falling parts of the shuttle.
"It's certainly possible if you can look at the trajectory and have any indication where something might have come off," said William Ailor, head of a center that tracks orbital and re-entry space debris for the Aerospace Corp., a defense contractor in El Segundo.
TRAJECTORY COMPLICATIONS
If altitude and velocity are known, he said, that data can be matched against the assumed size and shape of the pieces to help narrow the search. Wind and other weather conditions, however, seriously complicate such a project.
"It would take a while to come down, and the wind would blow it around a bit, too," Ailor said. "So it might not necessarily be right under the ground track."
The search on the ground has been a low-tech business of fielding tips and then driving around to check what has been found.
Landscape artist Cynthia DeBenedetti, 50, didn't think much of the small square of black foam she discovered on the front patio of her Woodside home Tuesday morning. But two friends persuaded her to contact authorities, who set up a quarantine area at DeBenedetti's home.
Sheriff's office spokeswoman Bronwyn Hogan displayed a bagged and tagged foam slab, about 3 inches by 3 inches and an inch thick, on Wednesday as she awaited further instructions from NASA and the EPA.
"It could be a very valuable piece of information about the fate of the Columbia shuttle," she said. "It's difficult to speculate. It could be anything."
MYSTERY METAL IN JOSHUA TREE
The San Bernardino sheriff's office was holding a mysterious small piece of metal that a resident of the Mojave Desert town of Joshua Tree found in his driveway Saturday.
Sheriff's department spokesman Chip Patterson described it as a burnt metallic object about 2 1/2 inches by 3 inches, found by local resident Robert Beggs after he had driven his car over it.
Beggs said he thought it was an ordinary scrap of trash at first, but then noticed how unusual it looked.
"I thought, 'Do I make a fool of myself?' Then I called the sheriff," Beggs said.
Patterson said the responding officer thought it was interesting enough to merit further study. The sheriff's office called NASA and described the object, and the space agency asked that it be kept in the agency's evidence locker. NASA said it would send a representative to inspect it today or Friday.
The town is near the 800,000-acre Joshua Tree National Park. "Anything could crash out there and nobody would ever find it," said Jay Zarkey, a park ranger.
Chronicle staff writers Wyatt Buchanan, Keay Davidson, Ryan Kim, Carl Nolte and Matthew B. Stannard contributed to this report. / E-mail Carl T. Hall at chall@sfchronicle.com
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