Mars MGS MOLA Digital Elevation Model (DEM) is based on data from the Mars Orbiter Laser Altimeter (MOLA; Smith and others, 2001), an instrument on NASA's Mars Global Surveyor (MGS) spacecraft (Albee and others, 2001). The DEM represents more than 600 million measurements gathered between 1999 and 2001, adjusted for consistency (Neumann and others, 2001, 2003) and converted to planetary radii. These have been converted to elevations above the areoid as determined from a Martian gravity field solution GMM-2B (Lemoine and others, 2001), truncated to degree and order 50, and oriented according to current standards. The average accuracy of each point is originally ~100 meters in horizontal position and ~1 meter in radius (Neumann and others, 2001). However, the total elevation uncertainty is at least ±3 m due to the global error in the areoid (±1.8 meters according to Lemoine and others [2001]) and regional uncertainties in its shape (G.A. Neumann, written commun., 2002).

This dataset accompanies the following papers: Adler et al. (2019) Hypotheses for the origin of the Hypanis fan-shaped deposit at the edge of the Chryse escarpment, Mars: Is it a delta? Icarus, 319, 885-908. doi: https://doi.org/10.1016/j.icarus.2018.05.021 Adler et al. (2022) Regional Geology of the Hypanis Valles System, Mars. JGR: Planets, doi: 10.1029/2021JE006994 Contents: - DEM mosaic of the Hypanis Valles and deposit region constructed from CTX, HRSC, and MOLA elevation data (geotiff). - Coverage map of CTX, HRSC, and MOLA footprints used (shapefile). - Previews of DEM (greyscale and color) and of coverage map (png) Description: We constructed a regional elevation mosaic (~17 m/pixel) in Adler et al. (2019) archived here. This mosaic incorporates 10 CTX digital elevation models (DEMs) of high resolution, 3 HRSC digital elevation models of medium resolution, and 1 MOLA global DEM of low resolution. Individual CTX DEMs were generated from the stereopairs listed below. Some individual products were calibrated and formatted with the USGS Integrated Software for Imagers and Spectrometers (ISIS) and then Ames Stereo Pipeline. Other products were generated with SOCET SET. All products were controlled to MOLA shot elevation data. Data incorporated: CTX stereopairs: ID (nadir-most), ID (resolution [m/pix]) P07_003631_1920, B09_013296_1920 (17.7 m/pixel) B17_016408_1913, G06_020443_1916 (18.5 m/pixel) J03_046104_1918, F05_037783_1918 (24.0 m/pixel) P08_004264_1912, B06_011951_1916 (17.7 m/pixel) G09_021788_1918, G11_022434_1918 (18.4 m/pixel) B17_016474_1915, B19_017186_1915 (20.2 m/pixel) D19_034816_1921, F01_036293_1920 (24.0 m/pixel) P13_006176_1918, F01_036293_1920 (18.2 m/pixel) D07_029845_1921, D07_029990_1921 (20.2 m/pixel) G21_026601_1918, P04_002774_1922 (20.2 m/pixel) HRSC DA4: H2134 (75 m/pixel) H2145 (50 m/pixel) H0894 (75 m/pixel) MOLA Elevation: 128 ppd Elevation (463 m/pixel) Funding: The work to create individual CTX stereopair DEMs was funded by UK Space Agency (UK SA) grants ST/ K502388/1, ST/R002355/1, ST/L00643X/1, and ST/R001413/1. We thank the Science and Technology Facilities Council for supporting science relating to ExoMars Rover landing site selection activities. The work to create a mosaic using these products and others was supported by grants from the NASA Mars Odyssey Project under a subcontract to ASU administered by the Jet Propulsion Laboratory/California Institute of Technology.

The presence of large outflow channels on Mars shows the importance of water in shaping the surface of the planet over geologic time. Chaotic terrain has been identified as the source region for flood waters responsible for carving out many of these channels. There are still many unanswered questions regarding chaotic terrains on Mars. Using the most up to date CTX, HRSC, and MOLA coverage, DEM and TIN models were used to investigate examples of smooth-topped chaotic terrains which include: Hydraotes Chaos, a crater pair in Hydaspis Chaos, Baetis Chaos, and Candor Chaos, all south of Chryse Planitia. The findings of this study suggest that the collapse of chaotic terrains is not regionally controlled. This study also suggests that the largest chaotic terrains do not require external heat sources to form. Finally, there is evidence that chaotic terrain forming events have occurred from the Middle Noachian to the Late Hesperian/Early Amazonian. This data set contains the raw data for the Chaotic terrains studied here. Specifically, for each terrain the following files are included: Baetis • Baeties+East_Statistics_All_Mesas o Spreadsheet of all Baetis and East Chaos mesas as well as some flat areas of the channel floor. • baetis+east_volume_depth_calc o Spreadsheet of volume calculations • Mosaic and DEM composites • Image of Mesa locations • TIN of Baetis and East Chaos • Volume surfaces used in volume calculation Candor • Candor_Statistics_All_Mesas o Spreadsheet of all Candor Chaos mesas as well as some flat areas of the floor. • Candor_volume_calc o Spreadsheet of volume calculations • Mosaic and DEM composites • Image of Mesa locations • TIN of Candor Chaos Hydaspis • Hydaspis_Statistics_All_Mesas o Spreadsheet of all Hydaspis Chaos mesas as well as some flat areas of the plateau. • Hydaspis_Calculation_Volume_Polygon o Spreadsheet of volume calculations • Hydaspis_Terrace_Measurements o Spreadsheet of elevation points of terraces • Mosaic and DEM composites • Image of Mesa locations • TIN of Hydaspis Chaos • Volume surfaces used in volume calculation Hydraotes • Hydraotes_Statistics_All_Mesas o Spreadsheet of all Hydraotes mesas as well as some flat areas of the plateau. • Hydraotes_Calculation_Volume o Spreadsheet of volume calculations • Hydraotes_Terrace_Elevation_Points o Spreadsheet of elevation points of terraces • Mosaic and DEM composites • Image of Mesa locations • TIN of Hydraotes Chaos

The enclosed table contains data collected for the 116 craters in Arabia Terra, Mars that are referred to in this work. All included craters are >10 km in diameter and were selected based on terminal dune fields observed in their interior. Crater wall slopes were measured downwind of each terminal dune field using elevation data from the Mars Orbiter Laser Altimeter (MOLA) 128 ppd interpolated elevation map. The slope of each crater wall was measured at the closest location downwind of each terminal dune field from a wind-parallel elevation transect originating at the rim of the crater and ending at the dune field. The depth of the crater was estimated by subtracting the elevation of the downwind margin of the dune field from the elevation of the crater rim measured downwind of the dune field. Wind streak type was determined by observing the albedo contrast between the wind streak (if present) and the surrounding landscape. For more information on methods and data analysis, see the m...

Data files and descriptions contained here:1. model_outputs: Hydrologic model output as shapefiles. Model described in detail in Horvath et al. (2016) and adapted for Mars in Horvath & Andrews‐Hanna (2017). This numerical model is a combined surface-subsurface hydrology model, with input evaporation potential (Ep) and precipitation (P) rates from Earth analog climates provided by the North American Land Data Assimilation Systems Phase-2 observation-based climate model. An annual precipitation of 300 mm/Mars year was assumed, uniformly distributed across the model domain. The total annual precipitation reaching either the surface or subsurface hydrologic system was determined using an Earth-based empirical method dependent on the aridity index (φ=Ep/P; Budyko, 1974). This approach relates the aridity index (φ) to the measured catchment discharge, deriving an estimate of the actual evaporative loss from the catchment. Subsurface flow was modeled using a finite-difference approximation to the groundwater flow equation, controlled by a depth dependent permeability (depth averaged permeability of 1 10-13 m2) and porosity (20%) distribution, and an assumed aquifer depth (10 km) based on the megaregolith aquifer model of Hanna and Phillips (2005). Runoff was modeled using a simple linear reservoir approximation which assumes catchment storage is linearly related to runoff. Lakes were allowed to naturally form on the surface where the contribution of groundwater, surface water, and precipitation directly to the lake balanced evaporation off of the lake surface. We focused on the aridity index dependence for modeled lake areas and elevations - here we provide model outputs with aridity indices of 1.5 (subhumid) and 3.5 (semiarid) (the two main climate conditions we focused on in the main paper).2. shapefiles.zip: For morphologic analysis, mapping was performed on an orthorectified and equalized basemap constructed from 6 m/pixel resolution Context Camera (CTX) imagery (Malin et al., 2007). For each crater within our region, we mapped all observed gully networks (GN) around the interior crater rim (at approximately 1:150,000 scale), which are small-scale branching erosional features. At the termination of each GN, we recorded the elevation using High-Resolution Stereo Camera (HRSC) digital elevation models (DEMs) where available (~10–30 m vertical resolution) (Jaumann et al., 2007), and the global 463 m/pixel resolution Mars Orbiter Laser Altimeter (MOLA; Smith et al., 2001) dataset otherwise (at ~100 m vertical resolution). We selected and mapped eighteen craters, six of which were previously identified as inferred paleolakes (Fassett & Head, 2008; Goudge et al., 2015; Grotzinger et al., 2014, 2015) .3. Roseborough_GRL_CraterCountData_SI_Resubmission_v0: We used the CraterTools ArcMap add-in to map crater ejecta and floors within the Gale crater region at approximately 1:100,000 scale, allowing us to capture craters at and below the 1 km diameter minimum benchmark (Kneissl et al., 2011). Crater diameters were then exported from ArcGIS. Here we report the surface area and the corresponding crater diameters for each surface we mapped (and include the crater stats figures (showing the derived modeled age) and our crater maps).

North Polar Layered Deposit spiral trough geomorphology metric data (2023Trough_AllData.xlsx) This dataset contains the trough metric data calculated from the 3,192 trough profiles analyzed in this study as an Excel file. The dataset is split into tabs; the All_Data tab, which contain the metric values calculated for all trough profiles, and regional tabs, based on the regions identified in Smith & Holt (2015), and labeled R1-7a (excluding R0, 6, and 7b, as they do not contain troughs that we mapped). Each profile is identified by a unique number ranging between 1-3,192, labeled as Trough_Profile in all tabs of the dataset. The All_Data tab contains location data for each trough profile analyzed in the study, recorded as the center latitude of the profile, labeled CENTROID_X, and the center longitude of the profile, labeled CENTROID_Y. The values of each trough metric for all trough profiles are also recorded in this tab, including equator-facing trough wall slope (labeled as EQ_Slope), pole-facing trough wall slope (labeled as Pole_Slope), equator-facing trough wall relief (labeled as EQ_Relief), pole-facing trough wall relief (labeled as Pole_Relief) the difference between the two relief values (labeled as Relief_Diff), trough width (labeled as Width), and trough depth (labeled as Depth). Each regional tab contains information on which trough each trough profile is connected to, labeled as Trough_Number, where profiles from the same trough have matching number values. The values of each trough metric for trough profiles present in the region identified by the tab’s title are also recorded in this tab, including equator-facing trough wall slope (labeled as EQ_Slope), pole-facing trough wall slope (labeled as Pole_Slope), equator-facing trough wall relief (labeled as EQ_Relief), pole-facing trough wall relief (labeled as Pole_Relief) the difference between the two relief values (labeled as Relief_Diff), trough width (labeled as Width), and trough depth (labeled as Depth).

North Polar Layered Deposit spiral trough profiles (trough_profiles.zip) This dataset contains the trough profile figures of the 3,192 trough profiles analyzed in this study as .PNG images. Each figure is titled with a unique number ranging between 1-3,192, identifying which profile the figure corresponds to (labeled as Trough Profile Profile_XXXX.txt, where the XXXX is the unique profile number). The x-axis of each figure is the extent of the trough profile in meters (labeled Extent (m)) and the y-axis of each figure is the elevation of the trough profile in meters (labeled Elevation (m)). The legend of each figure labels the original trough profile extracted MOLA data as a blue line, the polynomial curve fit to the original data as an orange line, the calculated minimum point on the profile as a green dot, the calculated left shoulder point on the profile as a red dot, and the calculated right shoulder point on the profile as a purple dot.

A cloud atlas of the Martian North Polar Layered Deposits using THEMIS VIS imagery from Mars years 26-35 (All_VIS_Images.xlsx) This dataset contains our updated cloud atlas for the 13,857 THEMIS VIS images analyzed in this study as an Excel file. Each image is identified by their product ID (V########), labeled as file_ID in the dataset, which are used to request that specific image from the Planetary Data System (PDS). Each image also has their corresponding Mars year, ranging from a value of 25-35 and labeled as mars_year in the dataset. Each image also has their solar longitude (Ls), which is the Mars-Sun angle measured from the Northern Hemisphere of Mars where the northern spring equinox is Ls=0, the northern summer solstice is Ls=90, the northern autumn equinox is Ls=180, and the northern winter solstice is Ls=270. The solar longitude is labeled as solar_long in the dataset. The location data for each image is also recorded in the dataset as the center latitude of the image, labeled center_lat, and the center longitude of the image, labeled center_long. The classification done by this study is also recorded in the dataset. This includes which NPLD region, based on the regions identified in Smith & Holt (2015), ranging from 0-7b, based on which region most of the image lied in and labeled NPLD Region. It also includes the image noise ranking (labeled Image Noise Rank in the dataset), which was used to quantify image quality, where we assigned a metric 0,1, or 2 to each image, gauging whether the image was visually clear enough to distinguish clouds. This metric was based primarily on if surface features could be visibly distinguished in the image (e.g., pitting, craters, trough wall layers, trough edges, striations, etc.). A ranking of 0 meant the surface features were clear and high-resolution; 1 meant surface features were visible but less resolved in some way (e.g., slightly blurred, washed out, blocked by some visual artifacts, etc.); 2 meant the surface features were not at all distinct or blocked out by large visual artifacts, and the image was classified as too noisy to credibly decide if clouds were or were not present. Images were then classified as either having cloud presence or absence, on a yes/no scale (labeled Clouds? (y/n?/n) in the dataset). To state “yes”, the cloud’s edge must be distinct from the NPLD surface, so as not to confuse the cloud with other surface features. If there was doubt if the feature is a cloud (e.g., due to a soft or no cloud boundary with the surface and/or image defects on top of the potential cloud), that image is classified as “no?” in this analysis, indicating there may be clouds present but we did not feel confident enough in the image quality to state “yes”. If clouds were identified they were classified into three broad categories in the following section labeled Cloud type, if visible: trough-parallel clouds (similar to the low-altitude clouds with an elongated structure located parallel to the NPLD troughs identified in Smith et al. (2013)), wispy clouds, and general cloudiness. When visible, other related cloud features were noted, such as the presence of undulations, or linear cloud structures. Images classified as “no?” had their possible cloud type identified as well, though the noise complicating the image was also noted.

This data set collects contours for the seasonal cap retreat published in Figure 3 of the associated article in Icarus. There are two zip files, one for text and one for shapefiles. See the methods for how to convert pixel locations to lat/lon coordinates. The Mars Color Imager (MARCI) camera on the Mars Reconnaissance Orbiter provides daily synoptic coverage that allows monitoring of seasonal cap retreat and interannual changes that occur between Mars Years (MY) and over the southern summer. We present the first analysis of this data for the southern seasonal cap evolution observed in MY 28, 29, 30 and 31 (2/2007 to 07/2013). Observation over multiple Mars years allows us to compare changes between years as well as longer-term evolution of the high albedo deposits at the poles. Seasonal cap retreat is similar in all years and to retreats observed in other years by both optical and thermal instruments. The cryptic terrain has a fairly consistent boundary in each year, but numerous small-scale variations occur in each MY observed. Additionally, numerous small dark deposits are identified outside the classically identified cyptic region, including Inca City and other locations not previously noted. The large water ice outlier is observed to retain seasonal frost the longest (outside the polar dome) and is also highly variable in each MY. The development of the cryptic/anti-cryptic hemispheres is inferred to occur due to albedo variations that develop after dust venting starts and may be caused by recondensation of CO2 ice on the brightest and coldest regions controlled by topographic winds. Ground ice may play a role in which regions develop cryptic terrain, as there is no elevation control on either cryptic terrain or the late season brightest deposits. Methods The data are strored as region of interest (ROI) text or evf shape files saved from the software ENVI. Each subfolder includes a png image of the contours over MOLA elevation. For the text files, each ROI is stored sequentially, the header notes the number of points in each ROI and then provides an x, y value for each point in the ROI. There are 12 ROIs for each year, every 10 degrees of Ls from 205 to 315. To convert these to lat lon, the image is a polar stereo projection 720 x 720 pixels. These reach 60 deg latitude at the edges of the frame, there are lower latitudes in the corners. 0,0 is the upper left by the Argyre impact basin and 720,720 the lower right. The center of the image (360,360) is the south pole(90S, 0). Use the pixel coordinate to determine the distance from the center of the image, this radial distance in converted to latitude using 30 deg/360 pixels. Longitude is similarly calculated using the angle from center top, which is 0 degrees with E quadrants note in Figure 1 of the associated Icarus article.

This repository contains:

1. Shapefiles of irregular polygonal ridge networks within mapping extent.
2. MOLA elevation and slope data extracted over mapped ridge networks.

CTX Stereo Digital Terrain Models (DTMS) and Orthorectified Images

See Readme for full details.

These data products were produced by Peter Grindrod and Joel Davis at the Natural History Museum, London.

They are shared here in an "as is" format. Please read the following information carefully.

Data Structure

The file "Index_ DTMs.xlsx" gives the image numbers and DTM filenames.

Data Sets

The exact products for each image pair include:

• 20 m/px DTM

• 20 m/px FOM (Figure of Merit - see below)

• 6 m/px orthoimage

Each image has been orthorectified using the relevant DTM. No data have been georeferenced to either another data set in this release, nor another Mars data set. Therefore care should be taken in the first instance in georeferencing as required. Although each DTM is tied to MOLA, there are likely to be some small elevation steps across DTM boundaries as a result of no bundle adjustment across DTMs. Finally, the quality of the DTMs is on the whole good, but noise levels vary – check the FOM and create a hillshade to ensure that each DTM is adequate for required use.

DTM Vertical Precision

The vertical precision of the DTMs can be estimated by using the method outlined in:

• Kirk, R. L., E. Howington-Kraus, B. Redding, D. Galuszka, T. M. Hare, B. A. Archinal, L. A. Soderblom, and J. M. Barrett, (2003), High-resolution topomapping of candidate MER landing sites with Mars Orbiter Camera narrow-angle images, J. Geophys. Res., 108(E12), 8088, doi:10.1029/2003JE002131.

• Kirk, R. L., et al. (2008), Ultrahigh resolution topographic mapping of Mars with MRO HiRISE stereo images: Meter-scale slopes of candidate Phoenix landing sites, J. Geophys. Res., 113, E00A24, doi:10.1029/2007JE003000.

File Format

Each file is available in geotiff format.

Credit

CTX images should be credited "Image: NASA/JPL-Caltech/MSSS”

Derived DTMs should be credited as "DTM: NASA/JPL-Caltech/MSSS/NHM”, and as follows, if possible

"The stereo DTM processing was carried out at the Natural History Museum, London"

Figure of Merit (FOM) explanation

If present, the FOM is a data product produced by the BAE Systems SOCET SET software, which is essentially a measure of the quality of the DTM.

The numerical value of each pixel corresponds to either how the pixel was generated or the confidence in the value.

Description The data archived here include specific results from geologic mapping studies of the Martian volcano Alba Mons associated with the publication 'Distribution and Morphology of Lava Tube Systems on the Western Flank of Alba Mons, Mars,' submitted to the JGR/ESS Special Issue on Planetary Caves: Exploring Planetary Caves as Windows into Subsurface Geology, Habitability, and Astrobiology.

These results were generated from analyses of imaging and topographic datasets acquired from spacecraft orbiting Mars, and were used to provide descriptions and quantitative characteristics of lava tube systems on the western flank of Alba Mons. Included here are two tables containing data associated with Figure 10 (map of lava tube segments) and Figure 11 and Tables 1 and 2 (associated morphologic and morphometric parameters) of the publication. More details of the study can be found in the publication.

Citation When using these data, please cite the following with the appropriate version number:

Crown, D.A., Scheidt, S.P., and Berman, D.C. (2022). Characteristics of Alba Mons lava tubes: Western flank study area (Version 5). figshare, doi.org/10.6084/m9.figshare.19758631.v5.

Data Files and Types Lava_Tube_Segments_Morphometry_A: ascii table, csv Lava_Tube_Segments_Morphometry_B: ascii table, csv

Data Spatial Reference Mars_2000_(Sphere) WKID: 104971 Authority: Esri Angular Unit: Degree (0.0174532925199433) Prime Meridian: Reference_Meridian (0.0) Datum: Mars_2000_(Sphere) Spheroid: Mars_2000_(Sphere) Semimajor Axis: 3396190.0 Semiminor Axis: 3396190.0 Inverse Flattening: 0.0

Bounding Box West: -130.0 deg East: -115.0 deg North: 47.5 deg South: 37.5 deg

Header Fields (Line 1) and Description Lava_Tube_Segments_Morphometry_A.csv ID: Feature ID of lava tube segment location Morphology: Morphology Type Start_Long: Longitude of Line Feature Start Start_Lat: Latitude of Line Feature Start Start_Z: Elevation of Line Feature Start End_Longitude: Longitude of Line Feature End End_Latitude: Latitude of Line Feature End End_Z: Elevation of Line Feature End Center_Longitude: Longitude of Line Feature Midpoint Center_Latitude: Latitude of Line Feature Midpoint Length_km: Length of Line Feature in kilometers

Lava_Tube_Segments_Morphometry_B.csv ID: Feature ID of lava tube segment location Slope_Deg: Surface slope of line segment, degrees Reg_Slope: Regional slope from 50 km MOLA grid, degrees Reg_Aspect: Regional slope aspect from 50 km MOLA grid, degrees Slope_diff: Difference between line feature and regional slope, degrees Bearing: Orientation of line feature, degrees Bearing_diff: Difference between line feature orientation and aspect of regional slope, degrees Longitude: Longitude of Line Feature Midpoint Latitude: Latitude of Line Feature Midpoint