This paper presents far-ultraviolet through mid-infrared (0.12–20 μ m) reflectance spectra of 27 fine-particulate (<10 μ m) terrestrial mineral samples, providing continuous spectra that cover an unusually broad spectral range and are of unusually fine particle size relative to most existing spectral libraries. These spectra of common geologic materials are useful for future applications that study the dust on various planetary bodies. Reflectance spectra were acquired of the samples at multiple laboratories at multiple wavelengths. All of the spectra were compared to one another to observe the general, common spectral characteristics (e.g., slope, band shape, and band depth), and the best segments of the spectra representing the mineral reflectance were scaled and spliced together to form a “Frankenspectrum” for each mineral that best represents the full wavelength range of far-ultraviolet, visible, near-infrared, and middle-infrared wavelengths. These scaled and spliced Frankenspectra, as well as the entire set of individual “original” reflectance spectra from each laboratory, are available in the Planetary Data System Geosciences Node.

The EXI instrument onboard the Emirates Mars Mission (EMM) spacecraft has been operating for a full Martian year. Using the elliptical orbit, EXI has observed the atmosphere and surface of Mars at both regional and global scales while providing a unique diurnal sampling. This diurnal coverage is available over much of the planet on a time scale of approximately ten days. The observations are typically taken in both the ultraviolet and visible: 260, 320, 437, 546, and 635 nm, with an effective spatial resolution of 2–4 km per native pixel. This presentation will provide an overview of EXI’s on-orbit activities and performance during the first Mars year of science operations, a summary of the diurnal behavior of seasonal trends in water ice clouds, and some examples of the combined analysis of EXI and Emirates Mars InfraRed Spectrometer (EMIRS) observations. More specifically, we will cover the following: The multiple types of observational modes employed, statistics of the images obtained and available in the EMM Science Data Center, and the radiometric performance of the camera as measured by the standard star observation program. The diurnal trends are associated with the seasonal behavior of water ice clouds through a Martian year, including the aphelion and perihelion seasons. The advantages and challenges of combining the EXI and EMIRS observations for atmospheric and surface studies, where the Instantaneous Field of View differs by one-to-two orders of magnitude. Funding for the development of the EMM mission was provided by the UAE government and to co-authors outside of the UAE by the Mohammed bin Rashid Space Center (MBRSC).

The Emirates Mars Mission (EMM) has a unique opportunity to observe the surface of Deimos, the smaller and outermost of the two moons of Mars. The origins of both Phobos and Deimos remain debated largely due to lack of available observations. The elliptical orbit of the EMM spacecraft, designed to provide comprehensive coverage of the martian atmosphere, allows for campaigns to periodically observe the moon. The slight adjustment of the orbit to move into a resonance with Deimos permits nominal science to continue. The campaign began in August of 2022 by undertaking a series of maneuvers to enable several flybys each stepping in and progressively attaining a closer distance to Deimos. Here, we will present the images collected by EXI of the targeted flyby (e.g., the flyby wherein the spacecraft achieves its closest distance to the moon). Observations for each flyby will include an initial image set at the start of the approach (red/green/blue/320 nm/260 nm), red images will be acquired at 1 min intervals during the approach, and when the spacecraft is at the closest point to Deimos a red/green/blue image set at full resolution, as well as a 320 nm image binned at 2×2 pixels, will be acquired. As the spacecraft leaves Deimos, the reverse observation strategy will be employed. These observations will help constrain the short-wavelength spectral properties and further characterize the geomorphology of this relatively understudied martian moon.

&lt;p&gt;Observations of clouds on Mars have long been studied to understand activity and the Martian water cycle. The Martian volcanoes have been shown to have associated cloud formations such as the Aphelion Cloud Belt (ACB) (Wolff et al., 2022), Orographic Clouds (Benson et al., 2006), and Perihelion Cloud Trails (Clancy et al., 2021). Previous studies provide insights into how these clouds appear and contribute to the atmosphere. The objective of this study is to provide a catalog of the life cycle of clouds observed by Emirates eXploration Imager (EXI) spatially (longitude, latitude) and temporally (Solar Longitude (Ls), local time) using the following wavelength channels 635nm (red), 546nm (green), 437nm (blue) and 320nm (ultraviolet which can be used to retrieve the water ice optical depth). To undertake this study, we identified the volcanic region (Olympus Mons and Arsia Mons) as the study region due to cloud presence in the area throughout the Martian year.&amp;#160; EXI is a camera on board the Emirates Mars Mission (EMM) &amp;#8211; Hope Probe. EXI acquires 12-megapixel images and has sufficient radiometric calibration for detailed scientific analysis (Jones et al., 2021). It was developed to better understand several critical constituents (e.g., dust, water ice clouds, etc) geographic and diurnal distribution in the lower atmosphere (Jones et al., 2021).&amp;#160;We will present the results of our database for clouds for Mars year 36.&lt;/p&gt; &lt;p&gt;&amp;#160;&lt;/p&gt; &lt;p&gt;Benson, J., James, P., Cantor, B., &amp; Remigio, R. (2006). Interannual variability of water ice clouds over major martian volcanoes observed by MOC.&amp;#160;Icarus,&amp;#160;184(2), 365&amp;#8211;371.&amp;#160;https://doi.org/10.1016/j.icarus.2006.03.014&lt;/p&gt; &lt;p&gt;Clancy, R. T., Wolff, M. J., Heavens, N. G., James, P. B., Lee, S. W., Sandor, B. J., Cantor, B. A., Malin, M. C., Tyler, D., &amp; Spiga, A. (2021). Mars perihelion cloud trails as revealed by MARCI: Mesoscale topographically focused updrafts and gravity wave forcing of high altitude clouds.&amp;#160;Icarus,&amp;#160;362, 114411.&amp;#160;https://doi.org/10.1016/j.icarus.2021.114411&lt;/p&gt; &lt;p&gt;Jones, A. R., Wolff, M., Alshamsi, M., Osterloo, M., Bay, P., Brennan, N., Bryant, K., Castleman, Z., Curtin, A., DeVito, E., Drake, V. A., Ebuen, D., Espejo, J., Farren, J., Fenton, B., Fisher, C., Fisher, M., Fortier, K., Gerwig, S., . . . Yaptengco, J. L. (2021). The Emirates Exploration Imager (EXI) Instrument on the Emirates Mars Mission (EMM) Hope Mission.&amp;#160;Space Science Reviews,&amp;#160;217(8).&amp;#160;https://doi.org/10.1007/s11214-021-00852-5&lt;/p&gt; &lt;p&gt;Wolff, M. J., Fernando, A., Smith, M. D., Forget, F., Millour, E., Atwood, S. A., Jones, A. R., Osterloo, M. M., Shuping, R., Al Shamsi, M., Jeppesen, C., &amp; Fisher, C. (2022). Diurnal Variations in the Aphelion Cloud Belt as Observed by the Emirates Exploration Imager (EXI).&amp;#160;Geophysical Research Letters,&amp;#160;49(18).&amp;#160;https://doi.org/10.1029/2022gl100477&lt;/p&gt;

The origins of the martian moons Phobos and Deimos remain enigmatic. Over the past decades a range of spacecraft have observed Phobos and Deimos in order to constrain their origin and evolutionary history, with proposals for their origins ranging from captured asteroids, to coalesced material from a giant impact on Mars. However, given the orbits these spacecraft and the orbits of Phobos and Deimos, Phobos has garnered the majority of the attention. Now thanks to the unique orbit of the Emirates Mars Mission (EMM) Hope spacecraft and a minor correction to its nominal science orbit, EMM has a unique opportunity to examine Deimos in great detail while fully retaining the originally designed mission to capture the variability in the martian atmosphere and exosphere.Following a minor orbital adjustment maneuver campaign beginning in August 2022, EMM will encounter Deimos multiple times, progressively observing the martian moon at lower and lower distances beginning in early 2023. These flybys culminate in the closest approach of ~150 km, observing the mostly illuminated, far side of Deimos. All three EMM instruments, the Emirates eXploration Imager (EXI), the Emirates Mars Infrared Spectrometer (EMIRS), and the Emirates Ultraviolet Spectrometer (EMUS) have observation sequences tailored to these flybys, collecting the highest resolution multispectral visible imaging data, thermal infrared surface temperatures and emission spectra, and ultraviolet spectra. When combined these instrument observations will provide key insights into the composition, morphology, and surface physical properties of the least studied martian moon, Deimos.

We present the initial views of the surface of Mars’ outer moon Deimos as observed by the Emirates Mars InfraRed Spectrometer (EMIRS), a Fourier transform infrared spectrometer observing from 6-50 µm with a spectral sampling of up to 5 cm-1. The primary science goal of the Emirates Mars Mission (EMM) is to study the variability in Mars’ atmosphere. As part of a coordinated campaign, the EMM spacecraft has adjusted its orbit into a resonance with Deimos, where it will periodically fly by the moon. Beginning the spring of 2023, EMIRS will collect numerous thermal infrared spectra of Deimos’ surface with a spatial resolution ranging from ~1-10 km. These observations will be the best-resolved infrared views of Deimos to date. Our planned observations achieve nearly complete global coverage of the surface, and span a range of local solar times, enabling investigations of both compositional and thermophysical properties. We will discuss these observations and initial findings.

&lt;p&gt;Martian mesospheric clouds are observed in the Martian atmosphere around 50 to 100 km. H&lt;sub&gt;2&lt;/sub&gt;O and CO&lt;sub&gt;2&lt;/sub&gt; clouds are known to form in the mesosphere. We present a systematic study of mesospheric clouds cataloged from images at a wavelength of ~180 nm acquired by the Emirates Ultraviolet Spectrometer (EMUS) instrument onboard the Emirates Mars Mission (EMM) Hope spacecraft. The study is focused on data from the mission&#039;s early Science Phase, when clouds are known to be abundant in aphelion season, and it provides insight into the distribution and pattern of mesospheric clouds, as well as showcasing corresponding near-simultaneous images of mesospheric clouds apparent in EMM&amp;#8217;s Emirates eXploration Imager (EXI) images at a longer UV wavelength. This work is expected to provide valuable information on understanding the coupling between the lower and upper atmosphere.&lt;/p&gt; &lt;p&gt;&amp;#160;&lt;/p&gt; &lt;p&gt;&amp;#160;&lt;/p&gt;

The Emirates Mars Mission (EMM) Emirates Mars Infrared Spectrometer (EMIRS) currently around Mars is acquiring remote measurements of the martian surface (temperature and composition) and lower atmosphere. EMIRS is a FTIR spectrometer covering the range from 6.0-100 µm (1666-100 cm‑1) with a spectral sampling as high as 5 cm-1 with a 5.4-mrad IFOV. The EMIRS optical path includes a flat 45˚ pointing mirror to enable one degree of freedom while the spacecraft provides the other to build up a 2-dimensional array of observations. The primary goals of EMIRS are to characterize the geographic and diurnal variability of key atmospheric constituents (water ice, water vapor, and dust) along with temperature profiles and surface temperature on sub-seasonal timescales EMIRS acquires data of the full martian disk and thus provides an integrated view of the martian surface and atmosphere in every spectrum. These observations include complete diurnal, seasonal, and geographic coverage of atmospheric properties, surface temperature, and also surface composition/mineralogy at wavelengths not regularly acquired of the martian surface. Due to the unique nature of the EMM orbit, EMIRS also collects data that spans the full local solar time range (all solar incidence angles), at multiple emission angles. These unique observations permit the interrogation of diurnal surface ices/frost, thermophysics (including sub-surface layering from both a seasonal and diurnal skin depth), surface roughness, and rock abundance in addition to the primary science goals. In this presentation, we provide an overview of the first surface observations, atmospheric retrieval algorithm, and first atmospheric science results from the aphelion-season observations taken by EMIRS over the first several months of EMM Science Phase operations.

Observations by the Emirates eXploration Imager (EXI) on‐board the Emirates Mars Mission are used to characterize the diurnal, seasonal, and spatial behavior of aphelion cloud belt during Mars Year 36 L S ∼ 30°–190°. Building from previous work with the Mars Color Imager (MARCI) onboard the Mars Reconnaissance Orbiter, we retrieve water ice extinction optical depth ( τ ice ) with an uncertainty ±0.0232 (excluding particle size effects). We connect EXI and MARCI using radiance and τ ice . Zonal and meridional diurnal trends are analyzed over 6–18 hr Local True Solar Time. The retrievals show large morning‐evening asymmetries about a minimum near 12 hr. The latitudinal distributions in early morning are extensive and particularly striking near mid‐summer. Comparisons to the Mars Planetary Climate Model show reasonable agreement with basic diurnal behavior, but noticeable departures include too much water ice in early morning, the general latitudinal extent, and behavior at smaller scales like the volcanoes and other topographically distinct features.

The Emirates Mars Mission (EMM) was launched to Mars in the summer of 2020, and is the first interplanetary spacecraft mission undertaken by the United Arab Emirates (UAE). The mission has multiple programmatic and scientific objectives, including the return of scientifically useful information about Mars. Three science instruments on the mission's Hope Probe will make global remote sensing measurements of the Martian atmosphere from a large low-inclination orbit that will advance our understanding of atmospheric variability on daily and seasonal timescales, as well as vertical atmospheric transport and escape. The mission was conceived and developed rapidly starting in 2014, and had aggressive schedule and cost constraints that drove the design and implementation of a new spacecraft bus. A team of Emirati and American engineers worked across two continents to complete a fully functional and tested spacecraft and bring it to the launchpad in the middle of a global pandemic. EMM is being operated from the UAE and the United States (U.S.), and will make its data freely available.

The EXI instrument is a camera onboard the EMM spacecraft, with a field a view capable capturing the full disk of Mars throughout its nominal science orbit. Though the use of its multiple band passes (220, 260, 320, 437, 546, 635 nm) and the effective spatial resolution (2–4 km per native pixel), EXI’s primary goal is to provide both regional and global imaging of the Martian atmosphere with diurnal sampling over much of the planet on a time scale of approximately 10 days. This presentation will provide an overview of EXI’s on-orbit instrument performance, a brief description of the observation strategy employed with the start of Science Operations (23-May-2021, Ls=49°), and the retrieval results of the ice optical depth and their diurnal behavior for the period of mid-spring through late-summer in the northern hemisphere. More specifically, the presentation will cover: Status of the instrument calibration and plans for on-going on-orbit monitoring of instrument performance, including radiometric errors. Plus, some guidance on interpreting the metadata of the EXI publicly released raw and calibrated images; Illustration of the various disk geometries sampled during an EMM orbit of Mars, and how such observations are combined to provide diurnal coverage of the illuminated portion of the disk/atmosphere; Overview of the ice optical depth retrieval algorithm, and its application to the data obtained since the start Science Operations with an emphasis on the behavior of the aphelion cloud belt; including the formation and decay phases.

The Emirates Mars Mission (EMM) – Hope Probe – was developed to understand Mars atmospheric circulation, dynamics, and processes through characterization of the Mars atmosphere layers and its interconnections enabled by a unique high-altitude (19,970 km periapse and 42,650 km apoapse) low inclination orbit that will offer an unprecedented local and seasonal time coverage over most of the planet. EMM has three scientific objectives to (A) characterize the state of the Martian lower atmosphere on global scales and its geographic, diurnal and seasonal variability, (B) correlate rates of thermal and photochemical atmospheric escape with conditions in the collisional Martian atmosphere, and (C) characterize the spatial structure and variability of key constituents in the Martian exosphere. The EMM data products include a variety of spectral and imaging data from three scientific instruments measuring Mars at visible, ultraviolet, and infrared wavelengths and contemporaneously and globally sampled on both diurnal and seasonal timescale. Here, we describe our strategies for addressing each objective with these data in addition to the complementary science data, tools, and physical models that will facilitate our understanding. The results will also fill a unique role by providing diagnostics of the physical processes driving atmospheric structure and dynamics, the connections between the lower and upper atmospheres, and the influences of these on atmospheric escape.

The Emirates Exploration Imager (EXI) on-board the Emirates Mars Mission (EMM) offers both regional and global imaging capabilities for studies of the Martian atmosphere. EXI is a framing camera with a field-of-view (FOV) that will easily capture the martian disk at the EMM science orbit periapsis. EXI provides 6 bandpasses nominally centered on 220, 260, 320, 437, 546, 635 nm using two telescopes (ultraviolet (UV) and visible(VIS)) with separate optics and detectors. Images of the full-disk are acquired with a resolution of 2–4 km per pixel, where the variation is driven by periapsis and apoapsis points of the orbit, respectively. By combining multiple observations within an orbit with planetary rotation, EXI is able to provide diurnal sampling over most of the planet on the scale of 10 days. As a result, the EXI dataset allows for the delineation of diurnal and seasonal timescales in the behavior of atmospheric constituents such as water ice clouds and ozone. This combination of temporal and spatial distinguishes EXI from somewhat similar imaging systems, including the Mars Color Imager (MARCI) onboard the Mars Reconnaissance Orbiter (MRO) (Malin et al. in Icarus 194(2):501–512, 2008) and the various cameras on-board the Hubble Space Telescope (HST; e.g., James et al. in J. Geophys. Res. 101(E8):18,883–18,890, 1996; Wolff et al. in J. Geophys. Res. 104(E4):9027–9042, 1999). The former, which has comparable spatial and spectral coverage, possesses a limited local time view (e.g., mid-afternoon). The latter, which provides full-disk imaging, has limited spatial resolution through most of the Martian year and is only able to provide (at most) a few observations per year given its role as a dedicated, queue-based astrophysical observatory. In addition to these unique attributes of the EXI observations, the similarities with other missions allows for the leveraging of both past and concurrent observations. For example, with MARCI, one can build on the ∼6 Mars years of daily global UV images as well as those taken concurrently with EXI.

Introduction: Numerous chloride–bearing deposits (~600) have been detected on Mars using data from the Mars Odyssey Thermal Emission Imaging System (THEMIS) [1-4], however, few have been studied in detail [1] and only one site [5] has been placed into the regional geologic context and stratigraphy. The chloride deposits appear to be thermophysically distinct and exhibit relatively featureless red spectral slopes in the visible near infrared (VNIR) and blue slopes superimposed on typical basaltic regolith in the mid–infrared (MIR), consistent with a mixture of anhydrous chlorides and silicates [1, 2]. The chlorides’ dominant formation mechanism is likely to be precipitation and/or evaporation from ponded surface runoff or groundwater upwelling [1, 4, 5]. In terrestrial settings, chloride deposits are associated with other alteration or evaporite phases, such as phyllosilicates and sulfates [4]. On Mars, however, additional evaporites have yet to be detected in association with the chloride deposits [3] and only a few occurrences of coexisting phyllosilicate and chloride salt deposits have been detected [1, 4, 6]. Investigations into the role of local and/or regional mechanisms that operated to deposit these unique materials will provide valuable insight into the timing and conditions of past aqueous events on Mars. In particular, this study focuses on the Noachis Terra region where the largest number of chloride deposits have been detected [1]. Data Reduction and Methodology: In this study, infrared (IR) spectra from CRISM image FRT00009ACE were atmospherically corrected for both gases and aerosols using the Discrete Ordinate Radiative Transfer (DISORT) model, following the methods of [8]. In the DISORT calculations, single-scattering albedo (SSA) values are acquired under the assumption that the lower boundary of the atmosphere is surface scattering light according to the Hapke function [9]. SSA spectra can be converted back into radiance coefficients comparable to laboratory reflectance [8] assuming incidence and emergence angles of 30° and 0°, respectively. In order to understand surface morphology and stratigraphy associated with local mineralogy (~10 km2 area), CRISM data were co-registered with imaging datasets and projected over rendered digital elevation/terrain models from the Context Imager (CTX) and from the HiRISE instrument (Figure 2b) onboard the Mars Reconnaissance Orbiter. CRISM spectral end–members: The relatively flat spectral signatures of anhydrous chloride mostly correspond to mixtures of halite (NaCl) and basaltic dust, likely of eolian origin [2, 6]. The lack of spectral features in the VNIR make the salts difficult to detect using common orbital techniques (i.e. CRISM browse parameters [7]). Through the use of a statistical principal–component approach, known as factor analysis and target transformation (FATT), CRISM spectral end– members were derived from the DISORT corrected image cube [8, 13] and fit to laboratory spectra using a linear least–squares model [11]. Best–fit FATT model results are considered to be the likely spectral end-members in the scene. Figure 1a shows best-fit models for hydrated mineral phases. Additionally, CRISM map projected targeted reduced data (MTRDR) data were acquired and ratioed spectra were collected for the various units of interest. MTRDR data aligns both long (IR) and short (VNIR) FRT spectral channels into a single mapprojected image, allowing for spectral analysis of prominent spectral signatures at shorter wavelengths. See Figure 1b for example.

Introduction: The Mariner 10 Infrared Radiometer (IRR) collected a low latitude transect of ~11 and 45 μm radiance data across the night side Mercury in 1974. These data provided an initial determination of the thermophysical properties of the mercurian surface, including determination of a low thermal inertia regolith, similar to Earth’s Moon [1]. Since Mariner 10 IRR, updated thermal models have been used to predict surface temperatures on Mercury [e.g., 2-6]. These studies included more detailed layering and temperature-dependent thermophysical properties. We have extended the analyses of previous work in two ways: 1) An up to date thermal model is used to interpret the relatively high spatial resolution IRR measurements across a wide range of longitudes and local times. To date, the comparison of recent thermal models to measurements has been limited, relying only on limited telescopic microwave emission measurements [2,4,5], or focusing entirely on modelbased results to better understand the thermal environment in Mercurian polar regions [3,6]. 2) With the more recent temperature data and associated thermal modeling of the Moon [e.g., 7,8] we are able to make detailed comparisons using the Moon as a framework to better understand and identify similarities and differences in their thermophysical properties. Surface temperatures were modeled using a 1-dimensional heat diffusion model. The model incorporates properties such as temperature dependent thermal conductivity and heat capacity and solar incidence angle dependent hemispherical albedo. Vertical layering in the model has customizable density, heat capacity, and thermal conductivity of individual layers. The model provides predicted surface and subsurface temperatures for any given input location and time, and can be applied to each Mariner 10 IRR measurement. Data Processing: The Mariner 10 radiometer dataset consists of brightness temperature measurements at ~1200 unique locations and was retrieved from NASA’s Space Science Data Coordinated Archive (NSSDCA). In order to convert the observed brightness temperature to surface kinetic temperatures, knowledge of the emissivity of the surface and its angular dependence is needed. We adjusted the surface emissivity based on the emission angle of the observation using lunar emission angle-dependent emissivity derived from Diviner data [9]. Our radiance and brightness temperature values closely match example radiance values and brightness temperatures listed in [10]. Results: We modeled surface temperatures to compare them to the retrieved surface temperatures along the IRR measurement transect. There is overlap between the forward-looking and aft-looking observations between ~70–90°E, acquired at different emission angles. After correction for emission angle-dependent emissivity, the temperatures between the two sets of observations match within 1K (Figure 1). NEΔT for IRR at 100K is 0.21K and the instrumentT for IRR at 100K is 0.21K and the instrument used full-aperture space and reference views to produce high quality, well-calibrated measurements. We focus on the 45 μm channel transect (Figure 1) covering much of the mercurian night from ~10– 165°E, and ~10°S–20°N. The derived surface temperatures range from ~100–130K, with local variations of ~5–10K. There are additional observations covering the early morning with both the 11 and 45 μm channels. Although they show useful information regarding surface roughness (e.g., [1]), they are not particularly sensitive to differences in thermophysical properties and are not shown here.