Contamination And Decontamination Of Spacecraft

One thing that it seems that NASA is always worrying about is contamination. We worry about contaminating outer space, we worry about contaminating the Moon and Mars, we worry about contaminating asteroids and finally and most importantly we worry about contaminating the very planet we live on, Earth. There are many people that believe that we have carefully avoided contamination and that we should be praised for the fine work that we have done in this area. I am not one of them. When I look at the entire program to avoid contamination, I have to say that it seems to me that the damage has already been done in many areas. The only manned mission to another heavenly body was our trip to the moon about 40 years ago. NASA will tell you that they took all sorts of precautions to avoid any contamination from the moon and when the astronauts hit the water they were taken out of their capsule and directly to quarantine

I would like you to think about this for a second. The capsule landed away from the aircraft carrier. The astronauts had to open it and get out of it and into a boat to be taken back to the carrier, walk across the deck and then and only then were they put into isolation. Was this a true precaution, or was this a show put on to convince the public that we were avoiding contamination, if there was any, from moon dust and such? Folks the damage was already done once that hatch was opened to the atmosphere. It was compounded when the astronauts got into the boat with the navy personnel and made worse when they were brought aboard the carrier and walked to the isolation chamber. I am not saying that there was anything harmful on the moon, but I am saying that if there was, we probably would have all caught it. When the astronauts got back into the lander to take off from the moon, there were complaints of dust everywhere. When they joined up with the module Columbia dust had gotten into everything.

Returning Apollo 11 Capsule
Photo Source: NASA

Quarantine
Photo Source: NASA

The Columbia had dust floating all around it on the trip back to earth. There is no doubt that this dust even got into the return capsule that splashed down. Thus when the hatch was opened some moon dust got into the atmosphere. It makes you wonder that if this is how things are treated, if we will ultimately do harm to ourselves by bringing back some organism from some newly explored world? There is no doubt that things should not be brought back, but tested in space first for any harmful attributes.

Somewhere along the line, scientists decided that they wanted to see what a comet was made of and that they were going to send a space probe to one that would bring back samples. The mission was called Stardust. The way that it worked was that a space vehicle, after getting sufficient energy by slingshot from going around the earth a few times flew into a comet's tail and let the particles in that tail hit the ship and also trapped some in a gel called aerogel. The gel pack was brought back to earth in a small capsule. Stardust was said to have been subject to level 5 planetary protection. That means that treatment was used to protect both the earth and the planetary body where the probe was going to. But even NASA stated that the risk of interplanetary contamination by alien life was judged low, not that it couldn't happen.

Stardust Mission
Photo Source: JPL/NASA

One of the reasons that they felt so confident in their procedures is that they felt that with particles hitting aerogel at 6100 meters per second, no life in the particle could survive. Maybe they don't have a right to assume this, since a totally new type of life could be found that is so hardy that it might survive A second point I would like to make is that aerogel is a type of material that cushions a blow. A few years ago scientists thought that no life could survive in water that is almost boiling, then they found life living in our oceans near magma vents that heated the water around them to almost the boiling point, so it doesn't pay for these guys to be too sure of themselves. Another thing that we have to think about is how to encase particles from another planet or body. How do we know what type of material to make the container out of? We made it out of materials that were able to contain earthly life. What if non terrestrial microscopic life could escape by eating seals and gaskets or even penetrating the material of the case itself?

The material from Stardust is on display at the Smithsonian and seems to be harmless, but did the return capsule ever get hit by the comets particles and if so, could some of them have been brought back to earth unharmed? There might have been tiny nooks and crannies in the return vehicle that they got into. The sample return capsule was at one end of the Stardust probe.

NASA sent a probe to get samples from our Sun and it was successful to a point. Apparently it got the samples, but the parachute didn't open on the trip back through earth's atmosphere and the probe slammed back into our planet, spreading its contents all over the Utah Test and Training Range. Is there anyone that could call this contamination control? The inner capsule with the samples in it was completely cracked and exposed to the air.

We have decided that before we send a probe it must be decontaminated. As a matter of fact there is a treaty, called the Outer Space Treaty that requires this. Once the Mars mission was being prepared, a biological decontamination program was carried out . The equipment and instruments were sterilized and then kept in a clean room. The Mars orbiter was not sterilized since it was going to remain in orbit. I do not know the exact procedure that is used in every instance to sterilize a space probe going to another planet, but I do know that if chemicals are used, they in themselves could be harmful to the environment of a planet.

Does it stand to reason that a country that has lost several nuclear weapons is capable of creating a fool proof decontamination program for space probes and even people? It always seems that some jerk is put in charge at the top, because he or she is either related to someone or has a relative that was a large contributor to a successful presidential or senatorial campaign. Many times these people have absolutely no experience or education that could be applied to what they were put in charge of. I actually saw this happen myself at the state level. It just shakes your faith in the entire system, especially when these people start making decisions just to show that they are the boss and have no idea of what they are doing.

Should we worry about contaminating ourselves? Why not, we have ruined the environment, probably brought about global warming and are allowing radioactive materials to pile up. The powers that be can't really be that worried about it or maybe they just don't care.