14 April 2009
This month, I am working at NASA’s Johnson Space Center in Houston, and I have to say, it’s a pretty cool place to work. Every morning I ride my bike past the pair of NASA T-38 jets that mark the entrance to Space Center Houston (the touristy part of JSC). I ride through the security checkpoint and on my left are a handful of rockets from the early days of space exploration. I pass mission control (as in: “Houston, we’ve had a problem.”), and buildings used to train the astronauts and test new technologies, and finally I get to building 31, where I work and where the moon rocks live. I can go from my desk to the door of the lunar vault without going outside. In fact, we did just that last week!
The lunar samples are stored in a big cleanroom, and to get in you have to put on a very stylish bunny suit. Here you can see me modeling the suit:
Before entering the clean room, we were also told to take off all gold or silver jewelry. This is because all gold and silver alloys (even 24K gold) have trace amounts of lead in them. Lead isotopes in the moon rocks are used to do radioisotope dating of the lunar samples, so absolutely no lead is allowed in the laboratory to avoid contaminating the samples. In fact, the lunar samples are only allowed to touch stainless steel, teflon, glass, and the high-purity nitrogen in the sample containers.
Also, the samples from each mission are restricted to the chamber for that mission. So, you would never see a rock from the Apollo 11 landing site in the Apollo 17 chamber. Again, this is to avoid cross-contamination. You don’t want to mistakenly think that rock A was found at the Apollo 17 site if it was really only collected at the Apollo 11 site.
The lab, chambers and vault are set up with increasing pressure. The vault is at a higher pressure than the sample chambers, the chambers are at a higher pressure than the cleanroom, and the cleanroom is at a higher pressure than the outside world. This means that if there is ever a leak, the more pristine air will blow toward the “dirtier” areas rather than the other way around.
Here’s a better view of the lab and the chambers. You can tell that the chambers are at a higher pressure because the gloves stick out into the room.
The lunar sample laboratory was initially used to painstakingly catalog every sample returned from the moon. This involved taking pictures and studying the geology and doing elemental analysis on each and every sample. These days the facility is mostly used to divvy up the lunar samples to send them to scientists. Each time the samples are split up, the curators take more pictures and record more detailed documentation. The curators are in the process of scanning all of the documentation and photos and making them available, but it’s a huge job so it will be a few more years. Still, there’s lots of great info about the samples available already if you follow the links on the right of the Astromaterials Curation page.
I asked whether this facility would have to be modified to accomodate the samples from the upcoming moon missions, and it sounds like it won’t be necessary for quite a while. There is room for a couple thousand kilograms of samples back in the vault right now. Eventually if that gets used up, it is likely that the Apollo samples would gradually be moved to one of the other curation facilities to make room for the new arrivals at JSC.
It’s very impressive to see everything involved in the curation of these priceless samples. It’s even cooler to look into a chamber and see a small grey lump of rock and realize that that rock has witnessed the history of the solar system. It has been shattered by impacts, irradiated by cosmic rays, and pock-marked by micrometeors. It sat on the surface of the moon and watched the continents on Earth collide and tear apart and the seas open and close. It watched mountain ranges rise and fall. And it witnessed life emerge and flourish. And then, one particularly clever (or particularly foolish) species of ape built a machine that launched a few particularly brave (or foolish) members of that species to the surface of the moon. There, one of them scooped up the rock and took it home.
They have been on Earth for forty years. Scarcely an instant to the rocks. And soon, as we return to the moon, more time-weary rocks will be joining them in a peaceful retirement in the stablest climate that any of them have ever experienced, in building 31: where the moon rocks live.