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SCENARIO ONE: A SPACEWALK
Take, for example, the idea of making a spacewalk to inspect the area of suspected damage. NASA officials said there was no proven method of doing that, since the two spacesuits on board were only there for repairs inside the payload bay. The crew had no jet backpacks to fly around the shuttle, and no robot arm to position themselves in sight of the bottom.
But the flight controllers Ive talked with after the disaster had no doubts they could have thrown together a workable plan in a day or two, if asked. They would have first completely checked it out in ground simulation facilities, such as the giant water tank where floating spacesuited astronauts mimic zero gravity, and then told the crew what to do.
The trick would be to break some safety rules, but not too many. One astronaut would unhook his or her safety line from the shuttle, and the shuttle would fire its thrusters to gently move about 200 feet away. It then would roll 180 degrees, turning its belly to the free-floating astronaut. Sure, he or she would probably be slowly turning end over end in space. But he or she would be able to eyeball the area of suspected damage and take digital still images and zoomed video. Then the shuttle would slowly roll another 180 degrees and move back to retrieve the astronaut, like a giant catchers mitt enveloping a pop foul.
The flight controllers I talked to were horrified by the Columbia disaster, but frustrated as well.
We never got a chance to do what we do best, one spacewalk expert lamented.
They had notebooks full of tricks, and minds trained to generate new ones as needed. They just didnt have time, this time, to even try.
But would such an inspection have revealed anything? Whether through an astronauts eyes or the lens of a small self-propelled space spy camera, through a spy satellite or ground-based surveillance telescope, any insight would only have been as good as the actual view. But what was there to see?
It appears that many of tiles came off the shuttle as it flew over California, indicating that perhaps few, if any, had originally been knocked completely free during launch. Many others may have been damaged but remained in place, which would deceive any visual inspection.
SPACE STATION OUT OF REACH
Flying over to the International Space Station, either to get inspected by its crew, or to seek shelter there, was never an option. Such a flight was physically impossible because the orbits of the station and the shuttle were in different directions through space. Where their paths crossed, they were at angles too sharp for the shuttles limited rocket fuel to turn the corner and match orbits.
This situation wasnt the arbitrary result of blind choice. The station is in a northerly orbit that allows access from Russias rocket base in Kazakhstan and that access is now the stations only lifeline. The 16-day Columbia mission was on a flight path designed to let it launch and land during daylight at Cape Canaveral, a powerful safety concern. The different requirements demanded incompatible orbits.
SCENARIO TWO: FLYING DIFFERENTLY
Was there a gentler way to fly Columbia back into the atmosphere? Cain was asked last week by reporters if there were some alternate flying tricks that might have relieved, at least in part, the thermal stress on the left wing.
For example, if the left wings thermal protection was known to be compromised, could the shuttle enter the atmosphere crabbed a little to the side? It would scorch the heck out of the right wing that tilted into the fire, but would it have made a difference for the injured left wing?
Its theoretically possible, Cain said, but added that his teammates didnt think it would have worked because such a move would have only a small effect on the heat load.
There are lots of things you can do, he said, but they dont necessarily solve your problem.
Worse, Cain said, You just lead to potentially other problems.
In this case, the good wing might have scorched through its own tiles, damaged its steering jets or suffered some other unanticipated damage. The balance of an unknown pile of new risks vs. an uncertain current risk would have been a decision nightmare.
SCENARIO THREE: RESCUE SHUTTLE
Another suggested scenario was rescue by another shuttle. If Columbia could have stayed in space long enough, and kept its crew alive long enough, perhaps the next scheduled shuttle mission could have reached it.
This sort of space rescue is the stuff of which science fiction movies are made and, in fact, one was, the 1969 film Marooned. And its the sort of impossible contingency that the Mission Control team (and their bolt-turner buddies on the launch crews at Cape Canaveral) could really sink their teeth into.
Maybe the next shuttle, scheduled for a flight in March, could have been accelerated to launch in less than two weeks. Major shortcuts and added risks would have been required. Fueling would have been more hazardous and equipment less thoroughly checked. Work shifts would have been long and would overlap, threatening procedural oversights.
Meanwhile, once it was determined that Columbia was badly even mortally wounded and could not safely return to Earth, it could be sacrificed to save its crew. Major systems could be powered down to conserve electricity (they would be ruined by the cold of space, but no matter).
Keeping the crew alive that long wouldnt have been easy. The long pole would have been the chemicals to absorb the astronauts exhaled carbon dioxide. This is the gas that kills people in closed spaces, such as children trapped in old refrigerators. Carbon dioxide accumulates in your blood and turns acidic, killing your brain cells.
There is only a finite supply of CO2-absorbing canisters on any shuttle mission. Even if old ones were dug out of the trash and CO2 levels were allowed to get so high as to be painful, a cold-blooded calculus could have told NASA that there wouldnt be enough air cleaning supplies for all seven astronauts to wait for the earliest-possible shuttle rescue. Thats when short-straw time arrives, and we move back into science fiction.
NO TIME
But on the day that Columbia was lost, there was no time to invent a new procedure or to try something utterly innovative and amazing that had been dreamed up in anticipation of such a bad day. The continuing agony of the Mission Control team, and of all space workers, is to ask what indicators they overlooked or misinterpreted, if any. Did they miss an opportunity to what-if their way around the crisis, to try something, anything, to break the chain of disaster? Or and it is a meager consolation was this just the kind of bad day that even Mission Control was powerless to forestall?
Author:
James Oberg, space analyst for NBC News, spent 22 years at the Johnson Space Center as a Mission Control operator and an orbital designer.
