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All sourcesNASA NTRSDOE OSTI
NASA NTRS2012

A Lunar L2-Farside Exploration and Science Mission Concept with the ORion Multi-Purpose Crew Vehicle and a Teleoperated Lander/Rover

A novel concept is presented in this paper for a human mission to the lunar L2 (Lagrange) point that would be a proving ground for future exploration missions to deep space while also overseeing scientifically important investigations. In an L2 halo orbit above the lunar farside, the astronauts would travel 15% farther from Earth than did the Apollo astronauts and spend almost three times longer in deep space. Such missions would validate the Orion MPCV's life support systems, would demonstrate the high-speed re-entry capability needed for return from deep space, and would measure astronauts' radiation dose from cosmic rays and solar flares to verify that Orion would provide sufficient protection, as it is designed to do. On this proposed mission, the astronauts would teleoperate landers and rovers on the unexplored lunar farside, which would obtain samples from the geologically interesting farside and deploy a low radio frequency telescope. Sampling the South Pole-Aitkin basin (one of the oldest impact basins in the solar system) is a key science objective of the 2011 Planetary Science Decadal Survey. Observations of the Universe's first stars/galaxies at low radio frequencies are a priority of the 2010 Astronomy & Astrophysics Decadal Survey. Such telerobotic oversight would also demonstrate capability for human and robotic cooperation on future, more complex deep space missions.

Orion Multi-Purpose Crew Vehicle (MPCV)↗
NASA NTRSDate not supplied

Transfers from TLI to Lunar Frozen Orbits with Applications to NASA’s CLPS & Artemis Programs

This paper will focus on trajectory transfers from trans-lunar injection (TLI) to lunar frozen orbits with applications to NASA’s Commercial Lunar Payload Services (CLPS) and Artemis Human Landing System (HLS) programs. For a CLPS application, the CS-3 mission is explored, which will deploy a communications relay satellite in lunar elliptical frozen orbit followed by landing a payload on the lunar farside during dawn. Given HLS will land a crew near the lunar south pole with lighting and timing requirements, the effect of varying the Earth-Moon transit duration to influence the approach direction upon landing will be explored.

lunar frozen orbits↗
NASA NTRS1972

Apollo 15 orbital science summary.

In this paper, summary results of the Apollo 15 orbital science payload are given, and some quick-look results of Apollo 16 are discussed. Geochemical instruments, consisting of gamma-ray, X-ray, and alpha particle spectrometers, have provided a chemical map of the lunar surface flown over by Apollo 15. The Laser Altimeter and frontside gravity data have shown some unexpected results with regard to the lunar shape, and provided new basis for understanding lunar mascons. A magnetometer, aboard the small subsatellite, has located magnetic anomalies principally on the lunar farside, and has shown that the small lunar magnetic field is smoother on the frontside than on the back. The mass spectrometer, in orbit aboard the Command and Service Modules, has measured unexpectedly large populations of molecules at orbital altitude (110 km), mostly due to spacecraft contamination. Two major camera systems have provided the first systematic metric quality photography and concurrent high resolution stereo coverage of the lunar surface.

Esenwein, G. F.↗
NASA NTRS2005

Lunar and Planetary Science XXXVI, Part 15

Contents include the following: Impact Metamorphism of Subsurface Organic Matter on Mars: A Potential Source for Methane and Surface Alteration. Preliminary Study of Polygonal Impact Craters in Argyre Region, Mars. Geochemistry of the Dark Veinlets in the Granitoids from the Souderfjarden Impact Structure, Finland: Preliminary Results. An Experimental Method to Estimate the Chemical Reaction Rate in Vapor Clouds: An Application to the K/T Impact. Study of the Apollo 16 Landing Site: Re-Visit as a Standard Site for the SELENE Multiband Imager. First X-Ray Observation of Lunar Farside from Hayabusa X-Ray Spectrometer. Lunar X-Ray Fluorescence Spectrometry from SELENE Lunar Polar Orbiter. Origin and Thermal History of Lithic Materials in the Begaa LL3 Chondrite. Evidence of Normal Faulting and Dike Intrusion at Valles Marineris from Pit Crater Topography. Evidence of Tharsis-Radial Dike Intrusion in Southeast Alba Patera from MOLA-based Topography of Pit Crater Chains. Are They Really Intact? Evaluation of Captured Micrometeoroid Analogs by Aerogel at the Flyby Speed of Stardust. Numerical Simulations of Impactor Penetration into Ice-Over-Water Targets. A Probable Fluid Lava Flow in the Hebes Mensa (Mars) Studied by HRSC Images. New Drill-Core Data from the Lockne Crater, Sweden: The Marine Excavation and Ejection Processes, and Post-Impact Environment. Cross-Sectional Profile of Baltis Vallis Channel on Venus: Reconstruction from Magellan SAR Brightness Data.

Source record↗
NASA NTRS2022

Unique Science from the Moon: An Overview

A new era of exploration of the low radio frequency universe from the Moon will soon be underway with landed payload missions facilitated by NASA. The science that could be accomplished from a lunar farside radio array is extensive and includes solar interplanetary radio bursts, Jovian and terrestrial natural radio emission, galactic synchrotron spectrum, exoplanets radio aurora, and doppler shifted radio emissions coming from the early formation of the universe just to name a few.

Lunar farside↗
NASA NTRS1992

Mariner 10 multispectral images of the eastern limb and farside of the moon

We present the first analysis of Mariner 10 multispectral image data for the eastern limb and farside of the moon. A new, rigorous calibration of these data is used that provides results that are consistent with independently derived data sets. From these newly calibrated data, a color ratio image (0.48/0.58 micron) is produced to show relative TiO2 abundances in mare units on the eastern limb and farside of the moon. Our results indicate that the farside lunar mare deposits examined have TiO2 contents that are intermediate to low (2.5 pct TiO2) relative to mare deposits on the nearside. We find no evidence for areally extensive deposits of either very low titanium or high to very high titanium basalts in these portions of the moon. Our findings support previous interpretations that the source regions for lunar mare basalts are laterally heterogeneous. Additionally, examination of highland units reveals a relatively blue region that corresponds with a previously proposed cryptomare, suggesting enhanced TiO2 for this unit. Finally, based on these Mariner 10 data, telescopic spectral data, Galileo multispectral image data, and lunar meteorite analyses we speculate that volcanism in farside mare deposits did not include high titanium basalts.

Robinson, Mark S.↗
NASA NTRS1977

Lunar gravity - A long-term Keplerian rate method

Nearside tracking data from Apollo subsatellites and Lunar Orbiter 5 are used to construct a model of the farside lunar gravity field. An indirect method of calculating the average effect of all the gravity anomalies which affect spacecraft orbits is reduced to a linear estimation problem by eliminating the integration of spacecraft dynamics. Doppler frequency shifts between the lunar satellite and earth-based tracking station are used to measure the line of sight velocity component between the orbiter and the tracker; gravity determination is then performed in a weighted least squares estimator which employs the orbital rates as data and formulates the normal equations using the associated Keplerian state. Simulations performed demonstrate that farside gravity features can be economically determined by use of gravity estimates obtained from long-period models of nearside orbiting tracks.

Ferrari, A. J.↗
NASA NTRS2014

Connecting Lunar Meteorites to Source Terrains on the Moon

The number of named stones found on Earth that have proven to be meteorites from the Moon is approx. 180 so far. Since the Moon has been mapped globally in composition and mineralogy from orbit, it has become possible to speculate broadly on the region of origin on the basis of distinctive compositional characteristics of some of the lunar meteorites. In particular, Lunar Prospector in 1998 [1,2] mapped Fe and Th at 0.5 degree/pixel and major elements at 5 degree/pixel using gamma ray spectroscopy. Also, various multispectral datasets have been used to derive FeO and TiO2 concentrations at 100 m/pixel spatial resolution or better using UV-VIS spectral features [e.g., 3]. Using these data, several lunar meteorite bulk compositions can be related to regions of the Moon that share their distinctive compositional characteristics. We then use EPMA to characterize the petrographic characteristics, including lithic clast components of the meteorites, which typically are breccias. In this way, we can extend knowledge of the Moon's crust to regions beyond the Apollo and Luna sample-return sites, including sites on the lunar farside. Feldspathic Regolith Breccias. One of the most distinctive general characteristics of many lunar meteorites is that they have highly feldspathic compositions (Al2O3 approx. 28% wt.%, FeO <5 wt.%, Th <1 ppm). These compositions are significant because they are similar to a vast region of the Moon's farside highlands, the Feldspathic Highlands Terrane, which are characterized by low Fe and Th in remotely sensed data [4]. The meteorites provide a perspective on the lithologic makeup of this part of the Moon, specifically, how anorthositic is the surface and what, if any, are the mafic lithic components? These meteorites are mostly regolith breccias dominated by anorthositic lithic clasts and feldspathic glasses, but they do also contain a variety of more mafic clasts. On the basis of textures, we infer these clasts to have formed by large impacts that excavated and mixed rocks from depth within the lunar crust and possibly the upper mantle. One of the key questions is whether the mafic materials are ferroan or magnesian, which remote sensing does not clearly distinguish, and if mafic, whether they might contain mantlederived components such as olivine (dunite). Many but not all have mainly ferroan mafic components, consistent with a ferroan crustal source that is complementary to the ferroan anorthositic suite and that represents primary magma-ocean-derived feldspathic crust. Meteorites such as ALH 81005 [5] and Shişr 161 [6], however, contain coarse-grained magnesian mafic clasts (Fig. 1a) derived from deeply seated and melted material associated with impact basins. Comparison to LP gamma-ray data [2] supports an origin for magnesian feldspathic meteorites such as these (e.g., Shişr 161) as shown in Fig. 1b. Sayh al Uhaymir (SaU) 169. Another distinctive but much less common composition is represented by relatively mafic impact-melt breccia that is rich in incompatible elements known as KREEP. These meteorites can be related to the western nearside Procellarum KREEP Terrane, especially through a combination of Fe and Th contents. Among the most enriched is SaU 169, which has been related to high- Th impact-melt breccia found at the Apollo 12 site [7]. Through detailed EPMA and ion microprobe analysis we have shown that these two rock types are related in age and origin.

Jolliff, B. L.↗
NASA NTRS2013

Can Fractional Crystallization of a Lunar Magma Ocean Produce the Lunar Crust?

New techniques enable the study of Apollo samples and lunar meteorites in unprecedented detail, and recent orbital spectral data reveal more about the lunar farside than ever before, raising new questions about the supposed simplicity of lunar geology. Nevertheless, crystallization of a global-scale magma ocean remains the best model to account for known lunar lithologies. Crystallization of a lunar magma ocean (LMO) is modeled to proceed by two end-member processes - fractional crystallization from (mostly) the bottom up, or initial equilibrium crystallization as the magma is vigorously convecting and crystals remain entrained, followed by crystal settling and a final period of fractional crystallization [1]. Physical models of magma viscosity and convection at this scale suggest that both processes are possible. We have been carrying out high-fidelity experimental simulations of LMO crystallization using two bulk compositions that can be regarded as end-members in the likely relevant range: Taylor Whole Moon (TWM) [2] and Lunar Primitive Upper Mantle (LPUM) [3]. TWM is enriched in refractory elements by 1.5 times relative to Earth, whereas LPUM is similar to the terrestrial primitive upper mantle, with adjustments made for the depletion of volatile alkalis observed on the Moon. Here we extend our earlier equilibrium-crystallization experiments [4] with runs simulating full fractional crystallization

Rapp, Jennifer F.↗
NASA NTRS1990

Genesis lunar outpost criteria and design

This design study--the third in the space architecture series--focused on the requirements of an early stage lunar outpost. The driving assumptions of the scenario was that the base would serve as a research facility and technology testbed for future Mars missions, a habitat supporting 12 persons for durations of up to 20 months, and would sustain the following five experimental facilities: Lunar surface mining and production analysis facility, construction technology and materials testbed, closed environmental life support system (CELSS) test facility, lunar farside observatory, and human factors and environment-behavior research facility. Based upon the criteria set forth in a previous programming document, three preliminary lunar base designs were developed. Each of the three schemes studied a different construction method and configuration. The designs were then evaluated in terms of environmental response, human habitability, transportability, constructability, construction dependability and resilience, and their suitability in carrying out the desired scientific research. The positive points of each scheme were then further developed by the entire project team, resulting in one integrated lunar outpost design.

Hansmann, Timothy↗
NASA NTRS1990

Astrophysics from the moon; Proceedings of the Workshop, Annapolis, MD, Feb. 5-7, 1990

The present conference on astrophysics from the moon encompasses the study of the Galaxy, external planetary systems, solar physics, stars and stellar evolution, the frontiers of Galactic, extragalactic, and cosmological astronomy, an introduction to lunar-based astronomy, concepts for lunar observatories including high-energy observatories, solar observatories, and observatories for particle astrophysics and gravitational studies. Specific issues addressed include the dynamics of Jovian atmospheres, planetary magnetospheres, flare physics, exobiology and SETI from the lunar farside, and the study of interactive stars, star formation, H II regions in absorption at low frequencies, and normal galaxies. Also addressed are the potential lunar investigation of quasars, the formation epoch, and the large-scale structure of the universe, and observational issues related to X-ray large arrays, optical interferometers, VLF radio astronomy, a UV-solar reflecting coronagraph, and a heavy-nucleus detector.

Mumma, Michael J.↗
NASA NTRS2015

Trajectory Design from GTO to Near-Equatorial Lunar Orbit for the Dark Ages Radio Explorer (DARE) Spacecraft

The trajectory design for the Dark Ages Radio Explorer (DARE) mission concept involves launching the DARE spacecraft into a geosynchronous transfer orbit (GTO) as a secondary payload. From GTO, the spacecraft then transfers to a lunar orbit that is stable (i.e., no station-keeping maneuvers are required with minimum perilune altitude always above 40 km) and allows for more than 1,000 cumulative hours for science measurements in the radio-quiet region located on the lunar farside.

Lunar orbit↗
NASA NTRS2003

Properties of the Hermean Regolith: New Optical Reflectance Spectra, Comparison with Lunar Anorthosites and Mineralogical Modelling - 5

We present new optical (0.4-0.65 micron) spectra of Mercury and lunar pure anorthosite locations, obtained quasi-simultaneously with the Nordic Optical Telescope (NOT) in 2002. A comparative study is performed with the model of Lucey et al. between iron-poor, mature, pure anorthosite (less than 90% plagioclase feldspar) Clementine spectra from the lunar farside and a combined 0.4-1.0 micron mercurian spectrum, obtained with the NOT, calculated for standard photometric geometry. Mercury is located at more extreme locations in the Lucey ratio-reflectance diagrams than any known lunar soil, specifically with respect to the extremely iron-poor mature anorthosites. Though quantitative prediction of FeO and TiO2 abundances cannot be made without a more generally applicable model, we find qualitatively that the abundances of both these oxides must be near zero for Mercury. We utilize the theory of Hapke, with realistic photometric parameters, to model laboratory spectra of matured mineral powders and lunar soils, and remotely sensed spectra of lunar anorthosites and Mercury. An important difference between fabricated and natural powders is the high value for the internal scattering parameter necessary to interpret the spectra for the former, and the requirement of rough and non-isotropically scattering surfaces in the modelling of the latter. The mature lunar anorthosite spectra were well modelled with binary mixtures of calcic feldspars and olivines, grain sizes of 25-30 micron and a concentration of submicroscopic metallic iron (SMFe) of 0.12-0.15% in grain coatings. The mercurian spectrum is not possible to interpret from terrestrial mineral powder spectra without introducing an average particle scattering function for the bulk soil that increases in backscattering efficiency with wavelength. The observed spectrum is somewhat better predicted with binary mixture models of feldspars and pyroxenes, that single-component regoliths consisting of either albite or diopside. Correct spectral reflectance values were predicted with a concentration of 0.1 wt% SMFe in coatings of 15-30 micron sized grains. Since reasonable cosmogonical formation scenarios for Mercury, or meteoritic infall, predict iron concentrations at least this high, we draw the conclusion that the average grain size of Mercury is about a factor of two smaller than for average returned lunar soil samples. The 0.6-2.5 micron spectrum of McCord and Clark is used to further limit the possible range of mineralogical composition of Mercury. It is found that an intimately mixed and matured 3 : 1 labradorite-to-enstatite regolith composition best matches both the optical and near-infrared spectra, yielding an abundance of approx. 1.2 wt% FeO and -approx. 0 wt% TiO2.

Warell, J.↗
NASA NTRS2015

Trajectory Design from GTO to Near-Equatorial Lunar Orbit for the Dark Ages Radio Explorer (DARE) Spacecraft

The trajectory design for the Dark Ages Radio Explorer (DARE) mission concept involves dropping the DARE spacecraft off in a generalized geosynchronous transfer orbit (GTO) as a secondary payload. From GTO, the spacecraft is then required to enter a near-equatorial lunar orbit that is stable (i.e., no station-keeping maneuvers are required) and yields the required number of cumulative hours (1,000) for science measurements while in the lunar farside radio quiet cone over a span of three years. Preliminary and expected results of the corresponding trajectory design are presented herein.

Lunar Orbit↗
NASA NTRS2017

Orbit Determination of the Lunar Reconnaissance Orbiter: Status After Seven Years

The Lunar Reconnaissance Orbiter (LRO) has been orbiting the Moon since 2009, obtaining unique and foundational datasets important to understanding the evolution of the Moon and the Solar System. The high-resolution data acquired by LRO benefit from precise orbit determination (OD), limiting the need for geolocation and co-registration tasks. The initial position knowledge requirement (50 m) was met with radio tracking from ground stations, after combination with LOLA altimetric crossovers. LRO-specific gravity field solutions were determined and allowed radio-only OD to perform at the level of 20 m, although secular inclination changes required frequent updates. The high-accuracy gravity fields from GRAIL, with <10 km spatial resolution, further improved the radio-only orbit reconstruction quality (<10 m). However, orbit reconstruction is in part limited by the 0.3-0.5 mm/s measurement noise level in S-band tracking. One-way tracking through Laser Ranging can supplement the tracking available for OD with 28-Hz ranges with 20-cm single-shot precision, but is available only on the nearside (the lunar hemisphere facing the Earth due to tidal locking). Here, we report on the status of the OD effort since the beginning of the mission, a period spanning more than seven years. We describe modeling improvements and the use of new measurements. In particular, the LOLA altimetric data give accurate, uniform, and independent information about LRO's orbit, with a different sensitivity and geometry which includes coverage over the lunar farside and is not tied to ground-based assets. With SLDEM2015 (a combination of the LOLA topographic profiles and the Kaguya Terrain Camera stereo images), another use of altimetry is possible for OD. We extend the 'direct altimetry' technique developed for the ICESat mission to perform OD and adjust spacecraft position to minimize discrepancies between LOLA tracks and SLDEM2015. Comparisons with the radio-only orbits are used to evaluate this new tracking type, of interest for the OD of future lunar orbiters carrying a laser altimeter. LROC NAC images also provide independent accuracy estimation, through the repeated views taken of anthropogenic features for instance.

Erwan Mazarico↗
NASA NTRS1974

Seismic effects from major basin formation on the Moon and Mercury

Grooved and hilly terrains are reported which occur at the antipode of major basins on the Moon (Imbrium, Orientale) and Mercury (Caloris). Order-of-magnitude calculations, for an Imbrium-size impact on the Moon, indicate P-wave-induced surface displacements of 10 m at the basin antipode that would arrive prior to secondary ejecta. Comparable surface waves are reported which would arrive subsequent to secondary ejecta impacts and would increase in magnitude as they converge at the antipode. Other seismically induced surface features include: subdued, furrowed crater walls produced by landslides and concomitant secondary impacts; emplacement and leveling of light plains units owing to seismically induced "fluidization" of slide material; knobby, pitted terrain around old basins from enhancement of seismic waves in ancient ejecta blankets; and the production and enhancement of deep-seated fractures that led to the concentration of farside lunar maria in the Apollo-Ingenii region.

Schultz, P. H.↗
NASA NTRS1975

Seismic effects from major basin formations on the moon and Mercury

Grooved and hilly terrains occur at the antipode of major basins on the moon (Imbrium, Orientale) and Mercury (Caloris). Such terrains may represent extensive landslides and surface disruption produced by impact-generated P-waves and antipodal convergence of surface waves. Order-of-magnitude calculations for an Imbrium-size impact on the moon indicate P-wave-induced surface displacements of 10 m at the basin antipode that would arrive prior to secondary ejecta. Comparable surface waves would arrive subsequent to secondary ejecta impacts beyond 1000 km and would increase in magnitude as they converge at the antipode. Other seismically induced surface features include: subdued, furrowed crater walls produced by landslides and concomitant secondary impacts; emplacement and leveling of light plains units owing to seismically induced 'fluidization' of slide material; and perhaps the production and enhancement of deep-seated fractures that led to the concentration of farside lunar maria in the Apollo-Ingenii region.

Schultz, P. H.↗