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Nighttime Lyman Alpha Mapping Project (LAMP) observations are used to investigate condensed volatiles at the south polar region of the Moon. This study incorporates LAMP data from the first ∼7 years of the mission and Diviner annual maximum temperatures to search for volatile signatures associated with H2O, NH3, and CO2. Other stable potential species, for example, SO2 and H2S, are not identifiable with the ultraviolet ratio‐temperature techniques and are not directly addressed in this study. We confidently detect a ∼20% increase in normalized Off‐band (175–190 nm) to On‐band (148–162 nm) albedo ratios (consistent with condensed surface volatiles) at temperatures below ∼115 K. Elevated normalized ratios extend to temperatures capable of supporting pure aforementioned ices over geologically long time scales. Although ∼115 K is consistent with H2O lifetimes of ∼1‐Myr, the presence of CO2 and NH3 are not uniquely delineated by the data trends with temperature. Future spectral modeling to appropriately identify the composition and abundance of these condensed volatiles remains necessary. Normalized albedo ratios are further analyzed for candidate species via maximum temperatures to inform the likelihood of ice signatures: H2O (70 K < T ≤ 115 K), NH3 + H2O (60 K < T ≤ 70 K), and CO2 + NH3 + H2O (T ≤ 60 K). We compare normalized albedo ratios across seven regions of interest (ROI), including Faustini, Shoemaker, Haworth, Cabeus, Amundsen, Nobile, and an unnamed region. Such comparisons allow for characterization of relative abundances of volatiles across the ROI important for their utilization in future crewed and robotic missions to the Moon. Plain Language Summary: Spectra taken by the Lyman Alpha Mapping Project ultraviolet spectrograph and surface temperature inferred from the Diviner radiometer (both onboard the Lunar Reconnaissance Orbiter) are used to investigate the presence of ices within craters at the Moon's south pole. We analyze spectral features at temperatures where H2O, NH3, and CO2 ice are stable. We find signatures consistent with condensed surface volatiles at temperatures below the H2O ice stability temperature, but are unable to confidently delineate NH3 and CO2 signatures. We further find that normalized signatures can be used to estimate the relative abundance of ice species across regions of interest. Volatile studies, such as the one presented here, are important for resource utilization in future crewed and robotic missions to the Moon. Key Points: Cold traps may support volatile reserves, which may be useful for resource utilization and for determining the origin of lunar volatilesAn increase in volatile signatures where H2O is thermodynamically stable is found; CO2, and NH3 are not confidently delineatedNormalized albedo differences provide insight on relative volatile species abundances between cold traps of interest [ABSTRACT FROM AUTHOR]

We employ nighttime observations from the Lyman Alpha Mapping Project (LAMP) ultraviolet (UV) spectrograph onboard the Lunar Reconnaissance Orbiter to investigate the presence of condensed water ice within lunar south pole cold traps. This study incorporates LAMP observations between 2009 and 2016, which more than doubles the number of observations from previous LAMP Permanently Shadowed Regions (PSRs) studies. In this study, we focus on cold traps within five south polar craters: Faustini, Shoemaker, Haworth, Cabeus, and Amundsen. An unnamed cold trap region adjacent to Haworth and Shoemaker was also investigated. We present On‐band (148–162 nm), Edge‐band (164–173 nm), and Off‐band (175–190 nm) albedo maps at 4‐km spatial resolution and far‐UV albedo spectra of cold traps at 2‐nm spectral resolution. We find Off‐band to On‐band albedo ratios (the UV wavelength ranges with high and low H2O ice reflectivity, respectively) within cold traps that are consistent with previous PSR studies. Spectral intimate mixture models considering 5 μm H2O grains and a range of regolith grain sizes (20–74 μm) with porosities between 0.3 and 0.75 yields abundances of ∼0.9–4.9 wt.%, where increasing the range of H2O and regolith grain sizes may increase the range of water abundance. We further find generally lower albedos within the cold trap regions than at the surrounding non‐cold trap regions across all wavelengths, consistent with increased regolith porosity within cold traps as suggested by Gladstone et al. (2012), https://doi.org/10.1029/2011JE003913. Plain Language Summary: Ultraviolet (UV) observations from the Lyman Alpha Mapping Project (LAMP) in orbit around the Moon are utilized to investigate the presence of H2O ice within areas of permanent shadow at the lunar south pole. The incorporation of more data (2009–2016) leads to increased accuracy when compared to previous LAMP investigations. We examine six regions at the lunar south pole within craters: Faustini, Shoemaker, Haworth, Cabeus, Amundsen, and an unnamed region. The ratio of two UV wavelength ranges are used as an indicator for the presence of H2O ice and were utilized to identify regions which may contain surface ice. Models of H2O and lunar regolith show that the observed UV spectral signatures are consistent with the presence of low amounts of water ice mixed with lunar regolith. Key Points: A new analysis of Lyman Alpha Mapping Project (LAMP) south pole measurements improves the spectral resolution to 2‐nm and incorporates additional years of acquisitionsFar‐ultraviolet band ratios within cold traps are consistent with a small amount of H2O intimately mixed with regolith and increased porosityThis initial analysis of an improved LAMP spectral map data set provides the foundation for investigating additional volatile species [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2009.01.016 Byline: V. Mangano (a), F. Leblanc (b), C. Barbieri (c), S. Massetti (a), A. Milillo (a), G. Cremonese (d), C. Grava (c) Keywords: Mercury; atmosphere; Spectroscopy Abstract: A long term plan of observations of the sodium exosphere of Mercury began in 2002 by using the high resolution echelle spectrograph SARG and a devoted sodium filter at the 3.5 m Galileo National Telescope (TNG) located in La Palma, Canary Islands. This program is meant to investigate the variations of the sodium exosphere appearance under different conditions of observations, namely Mercury's position along its orbit, phase angle and different solar conditions, as reported by previous observations in August 2002 and August 2003 [Barbieri, C., Verani, S., Cremonese, G., Sprague, A., Mendillo, M., Cosentino, R., Hunten, D., 2004. Planet. Space Sci. 52, 1169-1175; Leblanc, F., Barbieri, C., Cremonese, G., Verani, S., Cosentino, R., Mendillo, M., Sprague, A., Hunten, D., 2006. Icarus 185 (2), 395-402]. Here we present the analysis of data taken in June 29th and 30th and in July 1st 2005, when Mercury's true anomaly angle (TAA) was in the range 124-130[degrees]. The spectra show particularly intense sodium lines with a distinctive peak in emission localized in the southern hemisphere at mid-latitudes. This seems to be a persistent feature related to consecutive favorable IMF conditions inducing localized enhancements of surface sodium density. The comparison with previous data taken by Potter et al. [Potter, A.E., Killen, R.M., Morgan, T.H., 2002. Meteorit. Planet. Sci. 37 (9), 1165-1172] evidences a surprising consistency of the anti-sunward component, which appears to remain constant regardless of the changing illumination and space weather conditions at Mercury. Author Affiliation: (a) INAF-Istituto di Fisica dello Spazio Interplanetario, via Fosso del Cavaliere 100, 00133 Roma, Italy (b) Service d'Aeronomie, IPSL/CNRS, Universite Versailles Saint Quentin, Paris, France (c) Department of Astronomy, University of Padova, vicolo Osservatorio 2, 35122 Padova, Italy (d) INAF-Osservatorio Astronomico di Padova, 35122 Padova, Italy Article History: Received 18 November 2008; Revised 27 January 2009; Accepted 29 January 2009

Abstract: To complement Hisaki's ultraviolet monitoring of the Io plasma torus, a ground‐based campaign assembled a comprehensive data set at visible wavelengths with the ARC 3.5‐m telescope at Apache Point Observatory. This work concentrates on the bright S+ emissions in these data. Recurrent traits in the intensity and location are discerned as a function of Jovian longitude (λIII). The longitudinal brightness structure differs from past data sets in the visible but is broadly consistent with that of Io's auroral footprint and concurrent Hisaki extreme ultraviolet measurements. Positions of the ribbon feature with λIII confirm that it exhibits a radial wobbling motion that is lesser than the centrifugal limit along a given L‐shell. We also find that the radial separation between the cold torus and the ribbon is modulated as Jupiter rotates. The torus is displaced 0.13 RJ dawnward, on average, by an electric field with mean strength 3.8 mV/m, consistent with that inferred by analysis of Hisaki's dawn‐dusk brightness asymmetry. The lesser visible brightness asymmetry is uncorrelated to this field strength, however. S+ emissions are enhanced downstream of Io, principally at Jovian dawn. Io interacts with the densest region at specific Jovian longitudes and local times; near λIII ~130° and dawn the ribbon is farthest from Jupiter but still passes radially interior to the satellite. The electron density sweeping past Io and/or its radial proximity to the passing ribbon may also influence brightness, but S+ emissions are not governed by a single predominant driver. [ABSTRACT FROM AUTHOR]