BEAGLE: Biomass Enumerator and Geochemical/Limnological Explorer
BEAGLE is a project funded by NASA’s PSTAR program that will study the isolated, low biomass, yet remarkably diverse microbial community in the deep aquifer accessed through Wind Cave, Wind Cave National Park (WICA), South Dakota. The conditions of the lakes in this cave make them a unique analog environment for Europa. This project has the potential to obtain data of high scientific merit on microbial processes in the global manganese (Mn) geochemical cycle and carbon turnover, which will further the science and enable technological development for a variety of astrobiology targets. While the science side of this project is being spearheaded by PI Hazel Barton of the University of Alabama, Stone Aerospace is providing the technological development of the BEAGLE mobile science platform that will characterize the chemistry of the lakes and perform sampling operations.
Preliminary concept of BEAGLE Vehicle
Wind Cave is one of the oldest caves in the world, with the original cave-forming processes beginning almost 80 million years ago. At a depth of 122m, a series of lakes inundate almost a mile of cave passage, known as the Wind Cave Lakes (WCL). Rather than being of meteoric origin (i.e. rainwater that filtered down into the cave), the water in these lakes represents the Madison aquifer’s potentiometric surface.
Previous work by PI Hazel Barton in the WCL has revealed a fascinating ecosystem. While the water in the lakes contains among the lowest cell counts in the world, it also displays remarkable microbial diversity and is believed to be a Manganese-driven autotrophic system. This environment has many parallels to conditions believed to be present on ocean worlds such as Europa and Enceladus and is relevant to the study of manganese oxide as a potential astrobiological biosignature. However, the studies conducted to date have reached the limit of what is possible using commercial-off-the-shelf (COTS) components from the lake’s edge. The BEAGLE platform will allow for full physicochemical characterization of the WCL and strategic large-volume microbial sampling, greatly extending the possible research that can be conducted in this environment.
BEAGLE will be a semi-autonomous device that will map the lake and characterize the water chemistry in 3D, registered to a created map. Lake physiochemistry and cell counts will be obtained using a spooled instrument package that identifies sites for strategic large-volume, microbial sampling. BEAGLE will also employ a bi-directional low bandwidth wireless through-rock communication system to send data to the surface and receive instructions remotely.
Engineering development for the BEAGLE platform is currently underway. The platform will leverage existing technology developed by Stone Aerospace while meeting the sterilization requirements of COSPAR Category IV (Europa landing/Mars special region) Planetary Protection to allow operation within the lakes while protecting this unique environment.
A Challenging Environment
The isolation that makes the WCL a compelling site to study also makes it challenging to access. A trip to WCL involves crawling, climbing, and squeezing through approximately 3 km of cave, with passages as narrow as 22 cm, and is at least a 5-hour round trip for an experienced caver. Due to the restrictions and tight turns in many of the passages, all equipment will need to be transported in pieces, by hand, with final assembly occurring underground at the launch point.