The Astrobiological Significance of Impacts on the Moon Dirk Schulze-Makuch Center for Astronomy and Astrophysics, Technical University Berlin, Germany Introduction Water on the Moon An Early Lunar Hydrosphere? The possibility for the formation of ice deposits or Water seems to be more abundant in lunar rocks than previously other volatiles on the Moon has been suggested thought (6) and some of the rocks also contain phyllosilicates (7), previously, not only by degassing form the early evidence of an early exposure to liquid water. This observation Moon, but also by deposition from water-rich may be linked to vapor transport during degassing of a magmatic meteorite impacts near lunar poles (1). source region, or from a hybrid endogenic-exogenic process Temperatures have been estimated to not exceed when gases were released during an impacting asteroid or comet 40K in shadowed Moon craters allowing the (8). A more speculative suggestion would be the existence of an preservation of frozen water molecules over early Moon or Earth-Moon system hydrosphere, or perhaps a geologic time scales. Presence of ice has been significant accumulation of water after an impact. Evidence for verified based on data from various space missions larger-scale hydrological processes would be hard to find since (e.g., Figure 1) and radar measurements with the any resulting surface topography would be long erased by 4 Arecibo radio telescope. billion years of pounding with solar wind and cosmic radiation. Nevertheless, the idea should be tested as it would be beneficial Importance of Lunar Ice to know what happened to the water on the Moon early on, how much water the Moon retained, and for how long. Lunar water ice has the advantage that it can be used by future explorers to be converted into hydrogen and oxygen for rocket fuel. There have been several mining purposes being discussed such as ice-mining from the permanently shadowed areas. This can be accomplished either by a transport rover, drag line bucket, or a combination Figure 1. Map of hydrogen concentrations inferred to be water ice at the lunar north and south poles based on results from NASA's Lunar CRater of the two with the material being loaded into a Observation and Sensing Satellite and Lunar Reconnaissance Orbiter (purple highest concentrations, green lowest concentrations) (3). sealed vessel and heated by a solar furnace, while the released gasses are recovered and condensed into water (Figure 2). A better option would be to first separate the water from any organic endowment and any other particles that the ice Mining Water and Separating it from the Organics might harbor, which could be done using surfactant Figure 3. Device to separate clean water from organic residue. The Surfactant Modified Zeolite modified zeolite (Figure 3) or nanofilters (2). That (SMZ) filter was previously tested and proved extremely efficient removing organic compounds way the water could also be used for human due to its (1) cage-like porous structure, (2) hydrophobic properties, (3) and charge Figure 4. A very young lunar crater on the side of the Moon that faces consumption, plus the organic endowment may characteristics (5). SMZ has a distinct advantage over activated carbon in that regeneration of harbor a treasure trove of organic material. Not only away from Earth, as viewed by Chandrayaan-1's Moon Mineralogy the sorbent and recovery of the organic compounds is much easier. While activated carbon has Mapper would we be able to recover organic material from to be heated to desorb retained volatile organics, SMZ is readily regenerated by blowing air comets crashed on the Moon long ago, but these through the filter. No added heat source or an ice bath condenser are needed. References lunar ice-filled craters are the only location where we might find evidence of very early life on Earth. (1) Lowman, P.D. (2000) An Astrobiology Reconnaissance of the South Polar By discovering a rock fragment that was dislodged Removable Lid Region of the Moon, Goddard Space Flight Center. from Earth during a meteorite impact and landed on (2) Schulze-Makuch, D. (2013) Organic molecules in lunar ice: a window to the Vacuum the Moon, we might unravel the origin of life riddle, Chamber 2 early evolution of life on Earth. In Cellular Origins, Life in Extreme Habitats and Astrobiology 28, 115-125. possibly even detecting macromolecules before the Treatment of natural zeolites (3) Feldman, W.C. et al. (1998) Fluxes of Fast and Epithermal Neutrons from first life form originated on Earth. with large cationic Lunar Prospector: Evidence for Water Ice at the Lunar Poles. Science 281, 1496 Removable Lid Task 1: surfactants (quaternary Breathable amines) dramatically alters (4) Lowman, P.D. (2005) International Lunar Observatory: Suggested Instrument Figure 2. Set-up to mine water on the Moon. Complement, Goddard Space Flight Center (Code 698). Diaphragm their surface chemistries. (5) Schulze-Makuch, D., et al. (2003) Removal of viruses and bacteria from ground Material is loaded into a sealed vessel and cm 61 These large organic cations water by surfactant modified zeolite: field applications. Ground Water heated by a solar furnace while the released Chamber 1 Task 2: SMZ Filter exchange selectively with Monitoring and Remediation 24: 68-75. gasses are recovered and condensed into (6) Lin, Y. et al. (2017) Evidence for an early wet Moon from experimental Vapors native inorganic cations to water and stored in a storage tank for later form a stable, organic-rich crystallization of the lunar magma ocean. Nature Geosciences, DOI: use. The source of the sunlight (solar furnace) 10.1038/NGEO2845 30 cm 30 coating on the external (7) Drever, J.I. et al. (1970) Proceedings of the Apollo 11 Lunar Science could be from areas of uninterrupted solar surfaces of the zeolite. Collected Water Conference, 1, 341-345. power such as the rims of Shalkelton or the ICE Surfactant modification (8) Joy, K.H. et al. (2015) Identification of magnetite in lunar regolith breccia top of Malapert Mountain (4). allows the zeolites to sorb 60016: Evidence for oxidized conditions at the lunar surface. Meteoritics & nonpolar organic solutes Planetary Science, 50, 1157-1172. and anions, for which 20 cm 20 cm untreated zeolites have little affinity. Template provided by: “posters4research.com”.