Monday, January 29, 2007

Sad rememberances

This week represents one of the tougher weeks that NASA has ever had. NASA's worst three disasters all happened in a six day span (though spread out over 36 years).

On the late afternoon of January 27, 1967, Gus Grissom, Ed White, and Roger Chaffee, the crew of Apollo 1, were running a full scale test of the first Apollo capsule in preparation for a launch sometime that spring. To simulate a launch realistically, the cabin was filled with pure oxygen and pressurized. That evening, as the test was winding down, a spark caused by a short in the wiring occurred, and a fire was started. Since the atmosphere was complete oxygen, the fire was basically an explosion. Opening the door from the inside required the astronauts to remove 12 bolts and to pull the door inwards against the pressure of the interior air. The astronauts had no chance to escape and were killed by smoke inhalation within 20 seconds of the spark.

The day of January 28, 1986 was a snow day for my school in southeastern Pennsylvania. I forgot that the shuttle was supposed to launch that morning (in 6th grade I already loved space), so I was sledding in the backyard when I heard the phone ring. It was my mom, calling from work, to say she heard something about the shuttle landing in the Atlantic Ocean. Being a space nerd, I knew that the shuttle had plans to ditch in the ocean if something bad happened at launch, so I guessed (wrongly) that had happened. I went and turned on the TV to find out that, horribly, the shuttle Challenger had exploded during liftoff.

That morning had also been a cold one in Florida. Ice had formed around the launch pad; no shuttle had been launched in such cold weather. But the launch was to go on. Two previous launch attempts had been scrubbed, and this was a high-profile mission, as teacher ChristaMcAuliffe was on board and would be broadcasting her spaceflight to schools across the country. But the cold weather doomed the space shuttle. In the cold weather, the rubber that made up the seals between parts of the Solid Rocket Boosters became less pliable, and one of the O-rings failed to seal. Hot rocket gas escaped from the side of one of the boosters, eventually causing the external fuel tank to fail, which led todisintegration of the entire vehicle. All seven astronauts, Michael J. Smith, Dick Scobee, Ronald McNair, Ellison Onizuka, Christa McAuliffe, Gregory Jarvis, and Judith Resnik, lost their lives.

On February 1, 2003, I had just arrived in Tucson, Arizona to start a new job as a postdoctoral researcher there. I was temporarily renting a room in a graduate student's house while I waited for my own apartment to become free. I was going through my normal morning routine and turned on the TV to get the news. The story was alarming -- the Space Shuttle Columbia, returning from a two week mission, was "late" in showing up at Kennedy Space Center.

I knew this was disastrous. Space shuttles cannot be late -- once the rockets fire to bring it back in to the atmosphere, Sir Isaac Newton's gravity takes over. The shuttle's engines cannot fire during re-entry, so it cannot "circle" if there is bad weather or other problems. The fact that it was "late" meant that it was, in reality, lost.

The shuttle Columbia, unbeknownst to anybody, had a hole punctured in its wing during takeoff. During re-entry, super-hot gases (the same gases that burn up meteors) surround the spacecraft. The tiles on the out side of the shuttle protect it from that heat. (I remember seeing an episode of the Today show on a launch day many many years ago, and BryantGumbal was holding, in his bare hands, a shuttle tile that was glowing red-hot and being heated with a blowtorch.) Without protection from the hot gases, the metal on the interior of the wing melted, allowing even more gas in. Eventually the wing failed, and the shuttle tumbled out of control and disintigrated. Rick Husband, William McCool, Michael Anderson, David Brown, Kalpana Chawla, Laurel Clark, and Ilan Ramon, the seven crew members, were lost.

Space flight is dangerous. Human beings are not designed for space. So while it is very sad that these 17 astronauts (plus at least another four Russian cosmonauts, and many more from around the world killed in training accidents) died in space, they knew the dangers they were facing.

But the saddest part is that all of these three accidents were preventable. Before each accident, some people were worried about the root causes. And while we must remember that hindsight is always perfect, and remember that somebody is always worrying about something, and remember that we can never make spaceflight 100% safe, we must seek out the human failures that led to these disasters. We must make whatever cultural changes need to be made to prevent those human failures from causing any more deaths.

Sad to say, we will lose more people in space, someday. As private industry begins to send people into space, some of those will be killed, too. So now is the time for each of you to ask yourselves, what is an acceptable limit on losses? For what are we asking astronauts to risk their lives? How much risk should we allow private citizens who pay to go into space to be placed in?

These are questions that I cannot answer, because each person will have a different opinion. Over time, spaceflight will get safer and more reliable. We've seen this happen with airplanes. With boats. With cars. But also, we cannot be negligent and allow people to put their lives and those of others in needless risk. Having such discussions now, and not after the next disaster, should be the legacy of this week, of those we lost in our first tentative steps into the cosmos.

To read NASA administrator Michael Griffen's remarks on NASA's Day ofRemembrance, click here.

1 comment:

  1. Anonymous9:44 AM

    that was a very sincere thing for you to do, honoring all we have lost. i am one of probably hundreds that appreciate your kind and meaningful words...