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M S Robinson - One of the best experts on this subject based on the ideXlab platform.
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corrigendum to Lunar Reconnaissance Orbiter wide angle camera algorithm for tio2 abundances on the Lunar surface including low ti maria icarus 321 2019 141 147
Icarus, 2020Co-Authors: Bruce Hapke, Hiroyuki Sato, M S RobinsonAbstract:Abstract A critical typographical error and the value of a parameter in the new Lunar Reconnaissance Orbiter Wide Angle Camera TiO2 algorithm are corrected.
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Lunar Reconnaissance Orbiter wide angle camera algorithm for tio2 abundances on the Lunar surface including the highlands and low ti maria
Icarus, 2019Co-Authors: Bruce Hapke, Hiroyuki Sato, M S RobinsonAbstract:Abstract A new algorithm is proposed for estimating TiO2 abundance on the moon using Lunar reflectance values measured by the Wide Angle Camera on the Lunar Reconnaissance Orbiter spacecraft. The algorithm provides useful values for mature regoliths on the entire Lunar surface including highlands and low titanium maria. However, it underestimates the abundances of immature regoliths, so that the algorithm returns a lower limit for such features as young craters and rays.
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characterization of space weathering from Lunar Reconnaissance Orbiter camera ultraviolet observations of the moon
Journal of Geophysical Research, 2014Co-Authors: B. W. Denevi, A. K. Boyd, H. Sato, Bruce Hapke, M S Robinson, Ray B HawkeAbstract:We investigate the effects of space weathering at ultraviolet wavelengths using a near-global seven-band (321–689 nm) mosaic from the Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC). We confirm that for moderate- to high-iron compositions (≳ 5 wt % FeO), the steeply positive UV slope at wavelengths <415 nm shallows with increasing exposure to space weathering. We measure these differences in LROC WAC data as variations in the 321/415 nm ratio, which has low values for fresh craters in the mare and moderate-iron highlands. For low-iron highland compositions, the break in slope occurs at shorter wavelengths, and it is instead the 321/360 nm ratio that increases with exposure to the space-weathering environment, whereas the 321/415 nm ratio appears to be largely controlled by the degree of shock experienced during the impact. The effects of shock may be more important at highland craters because modest shock pressures result in the solid-state transformation of plagioclase to its glass equivalent, maskelynite, and can help distinguish between primary shocked ejecta and locally exposed fresh material in rays. While all of the “fresh” craters we examined have UV spectral properties consistent with substantial alteration due to space weathering, the UV spectra of Lunar swirls (magnetically shielded from the solar wind) are consistent with exposure of immature, crystalline material. Together these results suggest that Lunar space weathering is dominated by the solar wind and “saturates” in the UV at Is/FeO values of ~40 (submature).
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in orbit multi spectral image sharpness assessment for the Lunar Reconnaissance Orbiter wide angle camera
IEEE Aerospace Conference, 2014Co-Authors: P. Mahanti, D. Humm, R. Stelling, M S RobinsonAbstract:The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) began systematic Lunar imaging in January of 2010. WAC image maps and derived data products are allowing scientists to improve our knowledge of the Moon with science and engineering applications for future mission planning. The sharpness of the WAC images is an important measure of the camera performance over the duration of the mission time. Accordingly, a measure of the in orbit sharpness was achieved by computing the modulation transfer function (MTF) of the WAC multi-spectral optics from in-orbit Lunar limb images. Historically, Lunar limb images were used for MTF evaluation for imaging devices on Earth based satellites (e.g. NASA Earth Observer) as a supplement to other imaging targets, but were never used successfully for MTF computation for a Lunar Orbiter prior to this work (to the best of our knowledge). The proposed method is similar to the ISO 12233:2000 standard slanted edge gradient based method, but uses edge-fitting to obtain high resolution edge spread functions with the Lunar limb (that is not perfectly straight). Adaptive noise suppressed derivative computation and the Monte Carlo method for obtaining robust statistics, two other enhancements to standard MTF techniques, are also used in this work. Both cross-track and down-track MTFs were obtained and the results show that the LROC WAC meets and exceeds the MTF requirement of greater than 0.2 at the Nyquist frequency.
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mapping the apollo 17 landing site area based on Lunar Reconnaissance Orbiter camera images and apollo surface photography
Journal of Geophysical Research, 2012Co-Authors: I Haase, J Oberst, F Scholten, Marita Wahlisch, P Glaser, I P Karachevtseva, M S RobinsonAbstract:[1] Newly acquired high resolution Lunar Reconnaissance Orbiter Camera (LROC) images allow accurate determination of the coordinates of Apollo hardware, sampling stations, and photographic viewpoints. In particular, the positions from where the Apollo 17 astronauts recorded panoramic image series, at the so-called “traverse stations”, were precisely determined for traverse path reconstruction. We analyzed observations made in Apollo surface photography as well as orthorectified orbital images (0.5 m/pixel) and Digital Terrain Models (DTMs) (1.5 m/pixel and 100 m/pixel) derived from LROC Narrow Angle Camera (NAC) and Wide Angle Camera (WAC) images. Key features captured in the Apollo panoramic sequences were identified in LROC NAC orthoimages. Angular directions of these features were measured in the panoramic images and fitted to the NAC orthoimage by applying least squares techniques. As a result, we obtained the surface panoramic camera positions to within 50 cm. At the same time, the camera orientations, North azimuth angles and distances to nearby features of interest were also determined. Here, initial results are shown for traverse station 1 (northwest of Steno Crater) as well as the Apollo Lunar Surface Experiment Package (ALSEP) area.
Maria T. Zuber - One of the best experts on this subject based on the ideXlab platform.
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orbit determination of the Lunar Reconnaissance Orbiter status after seven years
Planetary and Space Science, 2017Co-Authors: Erwan Mazarico, Gregory A. Neumann, David E. Smith, M K Barker, Sander Goossens, Maria T. ZuberAbstract:Abstract 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
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simultaneous laser ranging and communication from an earth based satellite laser ranging station to the Lunar Reconnaissance Orbiter in Lunar orbit
Proceedings of SPIE, 2013Co-Authors: David R Skillman, Gregory A. Neumann, Ronald S. Zellar, Jan F. Mcgarry, Evan D Hoffman, Wai H Fong, Michael A Krainak, Leva Mcintire, Frederic M Davidson, Maria T. ZuberAbstract:We report a free space laser communication experiment from the satellite laser ranging (SLR) station at NASA Goddard Space Flight Center (GSFC) to the Lunar Reconnaissance Orbiter (LRO) in Lunar orbit through the on board one-way Laser Ranging (LR) receiver. Pseudo random data and sample image files were transmitted to LRO using a 4096-ary pulse position modulation (PPM) signal format. Reed-Solomon forward error correction codes were used to achieve error free data transmission at a moderate coding overhead rate. The signal fading due to the atmosphere effect was measured and the coding gain could be estimated.
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the transition from complex craters to multi ring basins on the moon quantitative geometric properties from Lunar Reconnaissance Orbiter Lunar Orbiter laser altimeter lola data
Journal of Geophysical Research, 2012Co-Authors: David M H Baker, Gregory A. Neumann, David E. Smith, Maria T. Zuber, J W HeadAbstract:United States. National Aeronautics and Space Administration (NASA Lunar Reconnaissance Orbiter Lunar Orbiter Laser Altimeter (LOLA) experiment (NNX09AM54G)
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Orbit determination of the Lunar Reconnaissance Orbiter
Journal of Geodesy, 2012Co-Authors: Erwan Mazarico, Gregory A. Neumann, David E. Smith, D. D. Rowlands, M. H. Torrence, F. G. Lemoine, Maria T. ZuberAbstract:We present the results on precision orbit determination from the radio science investigation of the Lunar Reconnaissance Orbiter (LRO) spacecraft. We describe the data, modeling and methods used to achieve position knowledge several times better than the required 50–100 m (in total position), over the period from 13 July 2009 to 31 January 2011. In addition to the near-continuous radiometric tracking data, we include altimetric data from the Lunar Orbiter Laser Altimeter (LOLA) in the form of crossover measurements, and show that they strongly improve the accuracy of the orbit reconstruction (total position overlap differences decrease from ~70 m to ~23 m). To refine the spacecraft trajectory further, we develop a Lunar gravity field by combining the newly acquired LRO data with the historical data. The reprocessing of the spacecraft trajectory with that model shows significantly increased accuracy (~20 m with only the radiometric data, and ~14 m with the addition of the altimetric crossovers). LOLA topographic maps and calibration data from the Lunar Reconnaissance Orbiter Camera were used to supplement the results of the overlap analysis and demonstrate the trajectory accuracy.
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impact melt volume estimates of small to medium sized Lunar craters from Lunar Reconnaissance Orbiter data
2011Co-Authors: E Mazarico, O S Barnouin, G Salamuniccar, Maria T. ZuberAbstract:Lunar Reconnaissance Orbiter DATA. E. Mazarico1,2, O. S. Barnouin3, G. Salamuniccar4,5, and Maria T. Zuber1. 1Massachusetts Institute of Technology, Department of Earth, Atmospheric and Planetary Sciences, Cambridge MA (mazarico@mit.edu); 2NASA Goddard Space Flight, Planetary Geodynamics Laboratory, Greenbelt MD; 3John Hopkins University Applied Physics Laboratory, Laurel MD; 4AVL-AST d.o.o., Av. Dubrovnik 10/II, HR-10020 Zagreb-Novi Zagreb, Croatia; 5Faculty of Electrical Engineering and Computing, University of Zagreb, Unska 3, HR-10000 Zagreb, Croatia.
Bruce Hapke - One of the best experts on this subject based on the ideXlab platform.
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corrigendum to Lunar Reconnaissance Orbiter wide angle camera algorithm for tio2 abundances on the Lunar surface including low ti maria icarus 321 2019 141 147
Icarus, 2020Co-Authors: Bruce Hapke, Hiroyuki Sato, M S RobinsonAbstract:Abstract A critical typographical error and the value of a parameter in the new Lunar Reconnaissance Orbiter Wide Angle Camera TiO2 algorithm are corrected.
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Corrigendum to “Lunar Reconnaissance Orbiter Wide Angle Camera algorithm for TiO2 abundances on the Lunar surface including low-Ti maria” [Icarus 321 (2019) 141–147]
Icarus, 2020Co-Authors: Bruce Hapke, Hiroyuki Sato, M. S. RobinsonAbstract:Abstract A critical typographical error and the value of a parameter in the new Lunar Reconnaissance Orbiter Wide Angle Camera TiO2 algorithm are corrected.
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Lunar Reconnaissance Orbiter wide angle camera algorithm for tio2 abundances on the Lunar surface including the highlands and low ti maria
Icarus, 2019Co-Authors: Bruce Hapke, Hiroyuki Sato, M S RobinsonAbstract:Abstract A new algorithm is proposed for estimating TiO2 abundance on the moon using Lunar reflectance values measured by the Wide Angle Camera on the Lunar Reconnaissance Orbiter spacecraft. The algorithm provides useful values for mature regoliths on the entire Lunar surface including highlands and low titanium maria. However, it underestimates the abundances of immature regoliths, so that the algorithm returns a lower limit for such features as young craters and rays.
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Characterization of space weathering from Lunar Reconnaissance Orbiter Camera ultraviolet observations of the Moon
Journal of Geophysical Research, 2014Co-Authors: B. W. Denevi, M. S. Robinson, A. K. Boyd, H. Sato, Bruce Hapke, B. Ray HawkeAbstract:We investigate the effects of space weathering at ultraviolet wavelengths using a near-global seven-band (321–689 nm) mosaic from the Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC). We confirm that for moderate- to high-iron compositions (≳ 5 wt % FeO), the steeply positive UV slope at wavelengths
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characterization of space weathering from Lunar Reconnaissance Orbiter camera ultraviolet observations of the moon
Journal of Geophysical Research, 2014Co-Authors: B. W. Denevi, A. K. Boyd, H. Sato, Bruce Hapke, M S Robinson, Ray B HawkeAbstract:We investigate the effects of space weathering at ultraviolet wavelengths using a near-global seven-band (321–689 nm) mosaic from the Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC). We confirm that for moderate- to high-iron compositions (≳ 5 wt % FeO), the steeply positive UV slope at wavelengths <415 nm shallows with increasing exposure to space weathering. We measure these differences in LROC WAC data as variations in the 321/415 nm ratio, which has low values for fresh craters in the mare and moderate-iron highlands. For low-iron highland compositions, the break in slope occurs at shorter wavelengths, and it is instead the 321/360 nm ratio that increases with exposure to the space-weathering environment, whereas the 321/415 nm ratio appears to be largely controlled by the degree of shock experienced during the impact. The effects of shock may be more important at highland craters because modest shock pressures result in the solid-state transformation of plagioclase to its glass equivalent, maskelynite, and can help distinguish between primary shocked ejecta and locally exposed fresh material in rays. While all of the “fresh” craters we examined have UV spectral properties consistent with substantial alteration due to space weathering, the UV spectra of Lunar swirls (magnetically shielded from the solar wind) are consistent with exposure of immature, crystalline material. Together these results suggest that Lunar space weathering is dominated by the solar wind and “saturates” in the UV at Is/FeO values of ~40 (submature).
B. W. Denevi - One of the best experts on this subject based on the ideXlab platform.
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Inflight Calibration of the Lunar Reconnaissance Orbiter Camera Wide Angle Camera
Space Science Reviews, 2016Co-Authors: P. Mahanti, M. S. Robinson, D. Humm, B. W. Denevi, E. Bowman-cisneros, A. K. Boyd, R. Stelling, H. Sato, S. E. Braden, S. M. BrylowAbstract:The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) has acquired more than 250,000 images of the illuminated Lunar surface and over 190,000 observations of space and non-illuminated Moon since 1 January 2010. These images, along with images from the Narrow Angle Camera (NAC) and other Lunar Reconnaissance Orbiter instrument datasets are enabling new discoveries about the morphology, composition, and geologic/geochemical evolution of the Moon. Characterizing the inflight WAC system performance is crucial to scientific and exploration results. Pre-launch calibration of the WAC provided a baseline characterization that was critical for early targeting and analysis. Here we present an analysis of WAC performance from the inflight data. In the course of our analysis we compare and contrast with the pre-launch performance wherever possible and quantify the uncertainty related to various components of the calibration process. We document the absolute and relative radiometric calibration, point spread function, and scattered light sources and provide estimates of sources of uncertainty for spectral reflectance measurements of the Moon across a range of imaging conditions.
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Characterization of space weathering from Lunar Reconnaissance Orbiter Camera ultraviolet observations of the Moon
Journal of Geophysical Research, 2014Co-Authors: B. W. Denevi, M. S. Robinson, A. K. Boyd, H. Sato, Bruce Hapke, B. Ray HawkeAbstract:We investigate the effects of space weathering at ultraviolet wavelengths using a near-global seven-band (321–689 nm) mosaic from the Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC). We confirm that for moderate- to high-iron compositions (≳ 5 wt % FeO), the steeply positive UV slope at wavelengths
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characterization of space weathering from Lunar Reconnaissance Orbiter camera ultraviolet observations of the moon
Journal of Geophysical Research, 2014Co-Authors: B. W. Denevi, A. K. Boyd, H. Sato, Bruce Hapke, M S Robinson, Ray B HawkeAbstract:We investigate the effects of space weathering at ultraviolet wavelengths using a near-global seven-band (321–689 nm) mosaic from the Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC). We confirm that for moderate- to high-iron compositions (≳ 5 wt % FeO), the steeply positive UV slope at wavelengths <415 nm shallows with increasing exposure to space weathering. We measure these differences in LROC WAC data as variations in the 321/415 nm ratio, which has low values for fresh craters in the mare and moderate-iron highlands. For low-iron highland compositions, the break in slope occurs at shorter wavelengths, and it is instead the 321/360 nm ratio that increases with exposure to the space-weathering environment, whereas the 321/415 nm ratio appears to be largely controlled by the degree of shock experienced during the impact. The effects of shock may be more important at highland craters because modest shock pressures result in the solid-state transformation of plagioclase to its glass equivalent, maskelynite, and can help distinguish between primary shocked ejecta and locally exposed fresh material in rays. While all of the “fresh” craters we examined have UV spectral properties consistent with substantial alteration due to space weathering, the UV spectra of Lunar swirls (magnetically shielded from the solar wind) are consistent with exposure of immature, crystalline material. Together these results suggest that Lunar space weathering is dominated by the solar wind and “saturates” in the UV at Is/FeO values of ~40 (submature).
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the wavelength dependence of the Lunar phase curve as seen by the Lunar Reconnaissance Orbiter wide angle camera
Journal of Geophysical Research, 2012Co-Authors: Bruce Hapke, B. W. Denevi, H. Sato, S. E. Braden, M S RobinsonAbstract:[1] The Lunar Reconnaissance Orbiter wide-angle camera measured the bidirectional reflectances of two areas on the Moon at seven wavelengths between 321 and 689 nm and at phase angles between 0° and 120°. It is not possible to account for the phase curves unless both coherent backscatter and shadow hiding contribute to the opposition effect. For the analyzed highlands area, coherent backscatter contributes nearly 40% in the UV, increasing to over 60% in the red. This conclusion is supported by laboratory measurements of the circular polarization ratios of Apollo regolith samples, which also indicate that the Moon's opposition effect contains a large component of coherent backscatter. The angular width of the Lunar opposition effect is almost independent of wavelength, contrary to theories of the coherent backscatter which, for the Moon, predict that the width should be proportional to the square of the wavelength. When added to the large body of other experimental evidence, this lack of wavelength dependence reinforces the argument that our current understanding of the coherent backscatter opposition effect is incomplete or perhaps incorrect. It is shown that phase reddening is caused by the increased contribution of interparticle multiple scattering as the wavelength and albedo increase. Hence, multiple scattering cannot be neglected in Lunar photometric analyses. A simplified semiempirical bidirectional reflectance function is proposed for the Moon that contains four free parameters and that is mathematically simple and straightforward to invert. This function should be valid everywhere on the Moon for phase angles less than about 120°, except at large viewing and incidence angles close to the limb, terminator, and poles.
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physical constraints on impact melt properties from Lunar Reconnaissance Orbiter camera images
Icarus, 2012Co-Authors: B. W. Denevi, S. J. Lawrence, T Tran, M S Robinson, O S Barnouin, Steven D Koeber, Brent W Garry, Ray B Hawke, L Keszthelyi, C M ErnstAbstract:Abstract Impact melt flows exterior to Copernican-age craters are observed in high spatial resolution (0.5 m/pixel) images acquired by the Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC). Impact melt is mapped in detail around 15 craters ranging in diameter from 2.4 to 32.5 km. This survey supports previous observations suggesting melt flows often occur at craters whose shape is influenced by topographic variation at the pre-impact site. Impact melt flows are observed around craters as small as 2.4 km in diameter, and preliminary estimates of melt volume suggest melt production at small craters can significantly exceed model predictions. Digital terrain models produced from targeted NAC stereo images are used to examine the three-dimensional properties of flow features and emplacement setting, enabling physical modeling of flow parameters. Qualitative and quantitative observations are consistent with low-viscosity melts heated above their liquidii (superheated) with limited amounts of entrained solids.
M. S. Robinson - One of the best experts on this subject based on the ideXlab platform.
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Corrigendum to “Lunar Reconnaissance Orbiter Wide Angle Camera algorithm for TiO2 abundances on the Lunar surface including low-Ti maria” [Icarus 321 (2019) 141–147]
Icarus, 2020Co-Authors: Bruce Hapke, Hiroyuki Sato, M. S. RobinsonAbstract:Abstract A critical typographical error and the value of a parameter in the new Lunar Reconnaissance Orbiter Wide Angle Camera TiO2 algorithm are corrected.
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Coordinates of anthropogenic features on the Moon
Icarus, 2017Co-Authors: Robert Wagner, M. S. Robinson, D. M. Nelson, Jeffrey B. Plescia, Emerson Speyerer, Erwan MazaricoAbstract:Abstract High-resolution images from the Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) reveal the landing locations of recent and historic spacecraft and associated impact sites across the Lunar surface. Using multiple images of each site acquired between 2009 and 2015, an improved Lunar Reconnaissance Orbiter (LRO) ephemeris, and a temperature-dependent camera orientation model, we derived accurate coordinates (
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geometric calibration of the clementine uvvis camera using images acquired by the Lunar Reconnaissance Orbiter
ISPRS - International Archives of the Photogrammetry Remote Sensing and Spatial Information Sciences, 2016Co-Authors: E J Speyerer, R Wagner, M. S. RobinsonAbstract:Abstract. The Clementine UVVIS camera returned over half a million images while in orbit around the Moon in 1994. Since the Clementine mission, our knowledge of Lunar topography, gravity, and the location of features on the surface has vastly improved with the success of the Gravity Recovery and Interior Laboratory (GRAIL) mission and ongoing Lunar Reconnaissance Orbiter (LRO) mission. In particular, the Lunar Reconnaissance Orbiter Camera (LROC) has returned over a million images of the Moon since entering orbit in 2009. With the aid of improved ephemeris and on-orbit calibration, the LROC team created a series of precise and accurate global maps. With the updated reference frame, older Lunar maps, such as those generated from Clementine UVVIS images, are misaligned making cross-mission analysis difficult. In this study, we use feature-based matching routines to refine and recalibrate the interior and exterior orientation parameters of the Clementine UVVIS camera. After applying these updates and rigorous orthorectification, we are able generate precise and accurate maps from UVVIS images to help support Lunar science and future cross-mission investigations.
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Inflight Calibration of the Lunar Reconnaissance Orbiter Camera Wide Angle Camera
Space Science Reviews, 2016Co-Authors: P. Mahanti, M. S. Robinson, D. Humm, B. W. Denevi, E. Bowman-cisneros, A. K. Boyd, R. Stelling, H. Sato, S. E. Braden, S. M. BrylowAbstract:The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) has acquired more than 250,000 images of the illuminated Lunar surface and over 190,000 observations of space and non-illuminated Moon since 1 January 2010. These images, along with images from the Narrow Angle Camera (NAC) and other Lunar Reconnaissance Orbiter instrument datasets are enabling new discoveries about the morphology, composition, and geologic/geochemical evolution of the Moon. Characterizing the inflight WAC system performance is crucial to scientific and exploration results. Pre-launch calibration of the WAC provided a baseline characterization that was critical for early targeting and analysis. Here we present an analysis of WAC performance from the inflight data. In the course of our analysis we compare and contrast with the pre-launch performance wherever possible and quantify the uncertainty related to various components of the calibration process. We document the absolute and relative radiometric calibration, point spread function, and scattered light sources and provide estimates of sources of uncertainty for spectral reflectance measurements of the Moon across a range of imaging conditions.
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Pre-flight and On-orbit Geometric Calibration of the Lunar Reconnaissance Orbiter Camera
Space Science Reviews, 2016Co-Authors: E J Speyerer, M. S. Robinson, D. Humm, P. C. Thomas, S. M. Brylow, R. V. Wagner, A. Licht, K. Becker, J. Anderson, M. TschimmelAbstract:The Lunar Reconnaissance Orbiter Camera (LROC) consists of two imaging systems that provide multispectral and high resolution imaging of the Lunar surface. The Wide Angle Camera (WAC) is a seven color push-frame imager with a 90^∘ field of view in monochrome mode and 60^∘ field of view in color mode. From the nominal 50 km polar orbit, the WAC acquires images with a nadir ground sampling distance of 75 m for each of the five visible bands and 384 m for the two ultraviolet bands. The Narrow Angle Camera (NAC) consists of two identical cameras capable of acquiring images with a ground sampling distance of 0.5 m from an altitude of 50 km. The LROC team geometrically calibrated each camera before launch at Malin Space Science Systems in San Diego, California and the resulting measurements enabled the generation of a detailed camera model for all three cameras. The cameras were mounted and subsequently launched on the Lunar Reconnaissance Orbiter (LRO) on 18 June 2009. Using a subset of the over 793000 NAC and 207000 WAC images of illuminated terrain collected between 30 June 2009 and 15 December 2013, we improved the interior and exterior orientation parameters for each camera, including the addition of a wavelength dependent radial distortion model for the multispectral WAC. These geometric refinements, along with refined ephemeris, enable seamless projections of NAC image pairs with a geodetic accuracy better than 20 meters and sub-pixel precision and accuracy when orthorectifying WAC images.
