Biological - AHAC review

It turns out that bacterial communities in the stratosphere were not popular for the Academic High Altitude Conference. In fact, I could only find one example of a paper even vaguely related to this concept. One project focused on a Cross-Continental High Altitude Balloon Mission for Astrobiological Research. The main focus of this project was to send different spores and biological materials up into near-space to test how the radiation affected them. The radiation that can be found in the upper stratosphere is actually similar to mars. This gives a glimpse into how biological material on Mars could be affected. This is not the Martian by any means but it is important to know how the food we eat or people living on the surface would fare after being exposed to different types of radiation.

They had 34 different field teams around the country in 10 different states who all sent the same microbe, Paenibacillus xerothermodurans, into the atmosphere. There were a good number of complications, including the Oregon team losing the payload in the Pacific ocean, but the majority of teams were able to collect their samples back after sending them up. All the viable samples were shipped to Cornell for analysis and the testing is underway. There has not been any more news from this project recently and they were last heard from in 2017. It can be assumed that their findings are still being put together or the project was not continued.

Again, this does not have a large correlation to our own project since they are sending up samples instead of collecting them. However, this is the only biology adjacent project found on the AHAC website.

I will also discuss NASA’s bioaerosol collectors which they use to take samples from the atmosphere. This is much more project adjacent and it could be useful for future projects to understand. They used a cascade impactor for their sampler. Here, they have a vacuum that creates constant air flow and takes in an air sample at a certain altitude. Then, the sample goes through a series of filters it impacts with each time have sample pores and catching different bacteria. This way they are able to test the size of bacteria while still getting the most out of a sample. They used a gelatinous filter for the same purpose as the quantity of samples. The collector could travel upwards of 13.7 km and they sent it up four different times.

They cultured every sample in order to find out the type of bacteria present at different altitudes. They were able to find samples of many different types of bacteria. However, their biggest problem remained their inability to stop cross-contamination from their lab equipment. They could never fully sanitize the collector as it was sent up and there was concern that some of the biomass they collecter came from lower altitudes.