NIMBUS: Near-Earth, Investigative Mycological & Bacteriological Ubiquity Surveyor

Abstract:

Traditional biosignature gases, such as oxygen (O₂), ozone (O₃), nitrous oxide (N₂O), & methane (CH₄) are gases that accumulate in Earth’s atmosphere in a fashion primarily driven by living entities.  Biosignature gases are particularly important to astrobiologists in their search for evidence of life on other planets.  On Earth, phosphine (PH₃) gas is produced primarily by either human activity or anaerobic microbial action.  Recently, astrobiologists detected high levels (parts per billion, ppb) of PH₃ in the atmosphere of Venus.  Such PH₃ concentrations suggest the possibility of microbial life on our sister planet.  On Earth, microbes are masterfully ubiquitous.  They broadly occupy numerous ecological niches, via their impressive metabolic diversities.  If microbes truly do occupy the Venusian clouds, can we say the same of our very own skyline?  Here we describe our efforts to construct an aerial drone (NIMBUS, or Near-Earth, Investigative Mycological & Bacteriological Ubiquity Surveyor) that is capable of hauling payload canisters axenically laden with a customized collection of nutrient media.  Canisters are extensively sterilized via an ethanol wash followed by overnight ultraviolet bombardment.  Our canister lids utilize magnetic seals to prevent in-transit contamination, and upon arriving at altitudinal destinations, a servo-motor breaches magnetic seals to permit ambient exposure to payload media.  Our current experimental design will collect aerial samples in 100-foot altitudinal increments, up to a 400-foot ceiling per FAA regulations.  Retrieved payload media will be incubated in aerobic and anaerobic conditions, followed by DNA extractions of cultured microbes for species identification via 16S rDNA (bacterial), ITS (fungal) profiling, or next-generation-sequencing (NGS) metagenomic analyses.