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Europa Station: Developing a Concept for Higher Fidelity Analog-Environment Testing of Candidate Ocean World Technologies

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Europa Station: Developing a Concept for Higher Fidelity Analog-Environment Testing of Candidate Ocean World Technologies Ocean Worlds (2019) 6039.pdf EUROPA STATION: DEVELOPING A CONCEPT FOR HIGHER FIDELITY ANALOG-ENVIRONMENT TESTING OF CANDIDATE OCEAN WORLD TECHNOLOGIES. W. C. Stone1; V. Siegel1; K. Richmond1. 1Stone Aerospace (3511 Caldwell Lane, Del Valle, Texas, [email protected]; [email protected]; [email protected] ). Introduction: We are developing a preliminary 6. Moving through the ocean to explore, characterize, concept for an Antarctic field camp facility to advance and sample in the search for life. development and testing of fully-integrated robotic Europa Station will provide operational environ- systems required for missions to explore the subsurface ments 3, 4, 5 and 6, while laboratory environmental of icy Ocean Worlds. The facility we propose – Europa chambers can be used to investigate environments 1, 2, Station – would be a multi-year technology develop- and 3. ment program and scientific field camp in Antarctica Europa Station Implementation. The Antarctic ice allowing for full-scale, long-term testing and validation sheet overlying unexplored subglacial lakes represents of space-capable technologies to penetrate kilometers the closest Earth analog for testing advanced Europa of ice, to break through into a liquid water environ- missions. The 4 km thickness of Antarctic ice can be ment, and to explore that environment for signs of life. viewed as the last 4 km of ice on Europa before ocean This same technology will also dramatically enhance breakthrough. As such, the ice sheet provides an ex- scientific access to subglacial lakes in Antarctica. We traordinary opportunity for mission simulations, testing are in initial planning stages for a community work- of life search protocols and algorithms, and assessing shop to further assess the merits and define the details the reliability of various concepts when subjected to of this idea, with the aim of submitting a report to long-term operations such as will be experienced on OPAG and contributing a white paper to the upcoming multi-year missions to Europa. We envision Europa Decadal Survey process. Station to be located in the Antarctic interior at a loca- Flight planning and space qualification of instru- tion where a minimum of 2,500 m and up to 4,000 m of ments are already underway for the Europa Clipper ice overlies a suitable subglacial lake. flyby mission. Advanced concept definition for a New power transmission technologies (e.g., using lightweight Europa lander is also moving forward. The high power lasers and fiber optics as well as high volt- next phases of technology development will need to age AC power transmission, novel insulators, and con- test a basic autonomous ice-penetrating vehicles ducting-fluid-based thermal power conversion) make it (known as “cryobots”) followed by a cryobot-deployed possible to create self-contained cryobots of reasonable autonomous underwater vehicle (AUV) to explore the size with relatively small field logistics footprints. sub-ice ocean. While AUVs are familiar to most scien- Spooling micro tethers from the vehicle allows the tists today, cryobots have only seen significant devel- borehole to refreeze behind the vehicle. Because opment in the last decade as a result of NASA-funded onboard spoolers can work in both directions, it be- research. comes possible for the vehicle to melt its way back to How does Europa Station address the need?: the surface at will, thus eliminating one of the greatest There are six critical environments in which sub-ice restrictions surrounding present Antarctic drilling tech- technology for Ocean World exploration will have to nologies. Furthermore, planetary protection require- successfully operate: ments have led to studies that show that a self- 1. The Starting Problem, in which a penetrator must contained cryobot, if pre-sterilized, will not forward- transition from the high-vacuum, ultra-cold environ- contaminate deeper ice. ment on the ice surface, to starting and entering a bore- These factors: novel power transmission; small lo- hole, through the eventual borehole closure behind it; gistics footprint; bi-directional travel; and presteriliza- 2. Brittle Ice Cruise transiting through ultra-cold, brit- tion not only allow for expedited Antarctic testing of tle cryogenic ice (temperatures <100K ); future space systems, they also open a doorway to rou- 3. Areas requiring identification of obstacles (impact tine and persistent subglacial lake access in Antarctica. debris, salt intrusions, etc.) or targets (brine layers or The development and testing of such vehicles at Euro- water-filled cracks and voids) and maneuvering around pa Station would significantly benefit both NASA or towards them as needed; planetary mission technology development and NSF 4. Ductile Ice Cruise transiting through more temperate polar science. ice (temperatures above 233K); 5. Breakthrough into the subsurface ocean; and .
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