THE MULTI-TEMPORAL OF PLANETARY IMAGE DATA MUTED NEW FEATURES TO STUDY DYNAMIC MARS T. Heyer1, H. Hiesinger1, D. Reiss1, J. Raack1, and R. Jaumann2

Fig. 1: MUTED user interface

INTRODUCTION ARCHITECTURE DATASETS

Multi-temporal observations are key to detect and analyze MUTED is based on free and open source software, and Metadata pertaining to more than 1.3 million images from surface changes and processes on Mars. Since the 1970s, consists of a three-tier architecture. Metadata of the various instruments including the Viking Orbiter (VO) [13], spacecraft observations have revealed that the surface of planetary image datasets are included from NASA’s the Mars Orbiter Camera (MOC) [14] on board Mars Global Mars is very dynamic [e.g., 1-3]. The modifications are Planetary Data System (PDS) into PostgreSQL database. Surveyor (MGS), the High Resolution Stereo Camera attributed to exogenic processes, including eolian activity Additional information, e.g., the number and span of (HRSC) [15] on board Mars Express (MEx), the THermal [4, 5], mass movement [6, 7, 8], the growth and retreat of overlapping images are derived for each image data EMission Imaging System (THEMIS) [16] on board Mars the polar caps [9, 10], and crater-forming impacts [11]. respectively. A Geoserver translates the metadata stored in Odyssey, the Compact Reconnaissance Imaging Observations of these variable features became possible the relational database into web map services (WMS) and Spectrometer of Mars (CRISM) [17], the Context Camera by the increasing number of repeated image acquisitions of web features services (WFS). All services are combined (CTX) [18], and the High Resolution Imaging Science the same surface areas. and visualized in the web-based user interface (Fig. 1). The Instrument (HiRISE) [19] on board the Mars MUTED comprises metadata of all major Mars missions user interface was built using HTML, PhP, and JavaScript Reconnaissance Orbiter (MRO) are integrated into the and enables scientists to quickly identify the spatial and and provides several features for data selection, filtering, database. The spatial resolution of the integrated images multi-temporal coverage of planetary image data from and visualization. The multi-temporal coverage, as well as varies from ~25 centimeters to several kilometers per pixel. Mars [12]. Images can be searched in temporal and spatial meta data and the spatial and temporal context of the A global coverage analysis reveals that high-resolution relation to other images at a global scale or for a specific images, are presented on the map or within a . images with a spatial resolution better than 25 meter/pixel region of interest. cover 99.9% of the surface of Mars (Fig. 2).

150 m 10 km 100 m 25 m 100 m

A HiRISE – ESP_026051_2160 NASA/JPL/ASU B HRSC – HI039_0000_ND ESA/DLR C HiRISE – ESP_053518_1955 NASA/JPL/ASU D HiRISE – ESP_037125_1315 NASA/JPL/ASU E HiRISE – ESP_022632_1670 NASA/JPL/ASU

DISTRIBUTION DATA-DRIVEN-SEARCH LOCATION-DRIVEN-SEARCH

Share areas of interest and data availability with others via The multi-temporal search enables users to find spatially Using global spectral, topographic or geological a link. The automatically generated permanent link stores overlapping images, which are separated by a user-defined information, users are able to define a region of interest the user defined area, datasets as well as filter options. temporal interval. Repeat images with a specified time and explore the local image coverage. All available orbital This enables a fast and convenient way to exchange interval (minutes, hours, days) or season (solar longitude) images can be filtered by date, season or spatial resolution. research areas and orbital images with other scientists or can be identified at a global scale. The spatial and temporal By selecting image footprints, metadata, including, e.g., save the current progress for work. An interactive context of the images is presented on the map or within a product ID, acquisition time, download links, as well as tutorial advices new users how to explore the multi- timeline. Additionally, queries can be listed and exported as high-resolution preview images, are presented. temporal coverage of Mars with MUTED and informs them text files. about the available data sets.

SCIENTIFIC APPLICATIONS

MUTED supports the identification of orbital images and their spatial and temporal context as a basis for various change detection analyses. In particular, the definition of a timespan between repeated images enables users to discover surface changes caused by very short-term and temporally highly variable processes, e.g., dust devils [A]. The number of images within a certain time period can be specified according to solar longitude, for example to observe seasonal changes and processes [B, C, D]. The number of overlapping images can be defined to ensure data availability, e.g., long-term changes of the surface of Mars [E]. MUTED has been used in recent projects on and recent changes of the martian surface [20, 21, 22]. In particular, the database has been used to identify multi- temporal high-resolution coverage and analyze the formation of slope streaks [20] and gullies throughout the martian year [21]. MUTED has also been used to support the data selection for geological mapping [22]. Due to continuous data acquisition by spacecraft, the amount of image data is steadily increasing and enables further comprehensive analyses of martian surface changes. The flexible structure of MUTED allows for a fast integration of upcoming data sets, e.g., from ESA’s Fig. 2: Global coverage of high-resolution images (spatial resolution better than 25 meter/pixel). ExoMars Trace Gas Orbiter (TGO) mission.

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