Space shuttle questions and answers

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The loss of the space shuttle Columbia has sparked difficult questions about how and why the breakup happened — but there are also more general questions that don’t relate directly to the investigation. Here are answers to some of the frequently asked questions about Columbia and the space program.

If NASA thought there might have been something wrong, couldn’t the crew have flown Columbia to the international space station for a checkup?

NASA says Columbia didn’t have the equipment to dock with the space station. In addition, Columbia was flying in an orbit that was about 100 miles (160 kilometers) lower than the station, with a different orbital inclination (39 degrees vs. 51 degrees for the space station). The shuttle was not carrying enough fuel to make what would have been a tortuous journey to the station.

Even for shuttle missions that are designed to include a space station stopover, the orbital mechanics are so precise that the launch window is limited to five minutes or less. For these reasons, it would have been virtually impossible for the shuttle to get to the space station.

Even if it were possible, it would be difficult to construct a scenario for an in-orbit repair operation or a rescue. If NASA knew there was a problem, Columbia could have stayed in orbit for an extra few days — perhaps long enough for the emergency launch of another shuttle, Atlantis. In a series of spacewalks, Columbia’s crew members could have been transferred over to the other shuttle. The operation would have required NASA to throw out its rule book, involving extraordinary risks.

I heard that some insulating foam from the shuttle’s external fuel tank may have hit the shuttle’s left wing after launch. Why didn’t they check for damage to the heat-shielding tiles?

During preparations for flight, an inch-thick layer of resin foam is sprayed onto the external fuel tank and hardened, in order to keep the liquid fuel cold and prevent ice buildup. The day after Columbia’s launch, engineers reviewed videotapes of the shuttle’s ascent and spotted what appeared to be a chunk of the foam, breaking off and hitting the shuttle.

An engineering analysis developed during the flight, based on similar incidents in the past, suggested that the foam could have damaged tiles on the left wing. Mission managers judged that such damage would not pose a serious risk.

A review of that judgment could become a key part of the investigation in the weeks ahead.

It’s questionable whether the crew or anyone on the ground could have gotten a direct view of the tile damage. Since Columbia was not being used for spacewalks for this mission, the robot arm was not aboard the shuttle this time around. A camera mounted on the robot arm might have been beneficial for doing an inspection; a spacewalk would have been far riskier and less useful.

Two of the shuttle’s astronauts, Michael Anderson and David Brown, had been trained to do an emergency spacewalk if necessary — and their EVA suits were aboard Columbia. But they had no equipment or safe procedure for inspecting the tiles beneath the wing for damage.

In the past, NASA has used military satellite imagery to look for damage to the shuttle’s tiles, but shuttle program manager Ron Dittemore said the images “were not very useful to us.”

Even if tile damage had been detected, Dittemore said, “we couldn’t do anything about it.” In the early years of the shuttle program, NASA had looked into developing a tile-patching kit that was basically a caulking gun. But the gunk undermined the performance of the tiles and never flew.

Could the flight have been aborted if NASA spotted the foam problem when it occurred?

The piece of foam came off the tank about 80 seconds after launch. If NASA mission managers had spotted the potential problem in real time and determined that it posed an unacceptable risk, they would have had several options for aborting Columbia’s flight.

In the first two and a half minutes after launch, the shuttle would have returned to a Kennedy Space Center landing strip or a backup strip along North America’s east coast. After that, the shuttle would have had another two and a half minutes to head for a landing at emergency runways in Spain, Morocco or Gambia. There are also emergency procedures for putting the shuttle into a lower-than-normal orbit.

It’s important to remember, however, that NASA did not regard the foam break-off as a mission-ending emergency — even when it was spotted after the fact.

Isn’t there an escape pod or an ejection-seat system on the shuttle?

No. For its first four test flights, Columbia had ejection seats for the two pilots, but those were removed once the testing phase was finished. The ejection seats could only be used at speeds of less than Mach 3 — much slower than the Mach 18 speeds at which Columbia was traveling when it broke up. Experts say no human could survive an ejection at the speed and altitude involved in Saturday’s tragedy.

After the Challenger explosion, engineers discussed the possibility of retrofitting the shuttles with escape pods, but NASA decided that the option would not increase survivability of an accident and might even compromise the shuttles’ structural integrity. In light of the Columbia breakup, the idea has sparked fresh debate.

NASA did install an emergency escape system that would enable the astronauts to parachute from the shuttle, but only during level flight at altitudes of 20,000 feet or less.

What was the shuttle Columbia doing during this mission? What happened to the experiments?

This was the first shuttle mission in three years devoted strictly to onboard science, with no spacewalks or space station visits involved. More than 80 experiments were conducted during the 16-day flight. Among the highlights:

Physicists studied how zero-gravity affected low-level combustion, an experiment that might have helped lead to leaner-burning automobile engines.

Astronauts collected scent molecules from a rose and an Asian rice flower in zero-gravity, in an experiment funded by the fragrance industry. Scientists found during a 1998 shuttle experiment that miniature roses gave off different scents in zero-G — and that those scents could be re-created synthetically on Earth to yield new fashion fragrances. The 1998 study resulted in a new perfume called “Zen” by Shiseido, as well as a body spray called “Impulse.”

Instruments made observations of the sun from space, which could have helped scientists gain new insights into the sun’s natural role in global climate change.

The crew observed atmospheric phenomena, including smoke and dust particles that could affect climate; and a type of electrical discharge that had never before been seen from space.

Arizona State University researchers sent up a project aimed at turning crew member urine and wastewater into clean water for drinking, cooking and bathing.

Shuttle crew members collected samples of their own blood, urine and saliva to detect possible bone loss, kidney stones, muscle loss or weakening of immune systems. Spiders, cancer cells, ants, carpenter bees, fish embryos, silkworms and rats were studied in space as well.

“I hope they can salvage something,” said Hideaki Moriyama, a University of Nebraska biochemist who supplied vials of proteins to the flight in hopes of finding clues to diseases like HIV-AIDS, Huntington’s and Alzheimer’s.

“It took more than four years to prepare those experiments,” Moriyama told The Associated Press.

Scientists will still be able to use the data that could be downloaded during the flight — but the samples that were being brought back to earth, including the fragrances, are likely lost forever.

What will happen to all the debris from the crash?

The fragments of hardware are being brought to investigators at Barksdale Air Force Base in Louisiana for identification — and eventually they will be taken to Kennedy Space Center for reassembly and analysis.

The remains of the crew are being turned over to a mortuary facility at Dover Air Force Base in Delaware for identification, primarily through DNA analysis, and then are being transferred to the next of kin.

In the wake of the investigation of the 1986 Challenger disaster, debris from that space shuttle was buried in an old missile silo at Cape Canaveral Air Force Station in Florida. Debris from Columbia would most likely be delivered to a similar fate.

How long will the shuttle fleet be grounded?

It’s too early to tell. After the 1986 Challenger explosion, it was almost three years before the shuttles flew again. It will certainly take months for investigators to finish their task, and if the other shuttles have to be modified to address safety concerns, the moratorium would have to be significantly extended.

What about the crew currently on the space station?

NASA says the three men aboard the international space station could remain there without shuttle support until at least June, with resupply by Russian cargo ships. In the longer term, there are three scenarios: The investigation could be finished up in time for a resumption of shuttle flights to the station. The Russians could provide more spaceships for crew transfers, perhaps with U.S. financial aid. Or the crew could get in the Russian-built emergency capsule currently docked to the station and ride it back down to Earth, leaving the station temporarily uninhabited.

Wasn’t NASA planning to mothball Columbia? Will they build another space shuttle to replace Columbia? What about the Enterprise?

In 2001, NASA considered putting Columbia in mothballs temporarily as a cost-saving measure. Nothing ever came of the idea, however, and Columbia was scheduled to take on a flight to the international space station this November as well as a Hubble Space Telescope servicing mission next year. On Sunday, Dittemore said any discussion about whether Columbia might have eventually been mothballed was now “academic.”

When Challenger was lost, NASA had to draw upon spare parts in order to build Endeavour, its replacement. Those parts are now harder to come by, and it seems unlikely that NASA would build another space shuttle like the other three.

There is yet another shuttle in storage — Enterprise, which was so named after a letter-writing campaign by “Star Trek” fans. Enterprise, the first shuttle ever built, was used for aerodynamic testing and was never equipped for space flight. After the tests were completed, some of Enterprise’s components were refurbished for use on other shuttles, and the shuttle was given to the Smithsonian Institution.

Enterprise will be put on display at the National Air and Space Museum’s Udvar-Hazy Center, which is scheduled to open at Dulles International Airport in December.

The Columbia tragedy may accelerate the development of NASA’s next-generation spaceship for human flight, a project known as the Orbital Space Plane. However, NASA hasn’t even settled on the design for such a craft yet. It could take a decade of development, at a cost of tens of billions of dollars, to create a brand-new fleet.

What’s NASA’s total budget? How much does each space shuttle flight cost?

President Bush boosted the budget request for NASA from the current $15 billion to $15.47 billion for fiscal year 2004, and that budget is likely to be adjusted to address concerns about shuttle safety.

Based on past budgets for human space flight, each shuttle flight costs $450 million to $500 million. At the time that the shuttles were built, each one cost roughly $2 billion.

What do we get from space flight? How do we know it’s worth the cost and the risk?

NASA and its supporters often highlight the medical and technological spin-offs that result from space experimentation.

“We’re not up there in space just to joyride around,” retired senator-astronaut John Glenn said on NBC’s “Meet the Press” on Sunday. “We’re up there to do things that are of value to everybody right here on Earth. It’s not always just looking on out and planning to go to Mars.”

For example, Glenn said, one of the studies on Columbia could have led to the development of techniques to prevent the transfer of cancer cells from the prostate gland to other tissues — which he said caused the death of his father.

“Maybe we can stop that,” Glenn said.

Others say space exploration contributes to our scientific understanding of Earth, life and the universe — as seen through the eyes of space travelers, Earth-observing satellites, deep-space probes and the Hubble Space Telescope. Without the shuttle spacewalks, Hubble’s vision would have been permanently clouded.

Still others point to planetary threats ranging from asteroid strikes to global warming to global terrorism, and say that finding a second home beyond Earth is a matter of species survival.

“There may be only a brief window of opportunity for space travel during which we will in principle have the capability to establish colonies,” Princeton astrophysicist J. Richard Gott III wrote in the journal Nature a decade ago. “If we let that opportunity pass without taking advantage of it, we will be doomed to remain on the Earth, where we will eventually go extinct.”

The Associated Press contributed to this report.