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Spatial Infrastructure for the OSIRIS-Rex Sample Return Mission March 23, 2016

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Spatial Infrastructure for the OSIRIS-Rex Sample Return Mission March 23, 2016 Spatial Infrastructure for the OSIRIS-REx Sample Return Mission March 23, 2016 Dani DellaGiustina O.S. Barnouin, M.C. Nolan, C.A. Johnson, L. Le Corre, and D.S. Lauretta Lunar & Planetary Sciences Conference The Woodlands, Texas OSIRIS-REX DEFINED • Origins . Return and analyze a sample of pristine carbonaceous asteroid regolith • Spectral Interpretation . Provide ground truth for telescopic data of the entire asteroid population • Resource Identification . Map the chemistry and mineralogy of a primitive carbonaceous asteroid • Security . Measure the Yarkovsky effect on a potentially hazardous asteroid • Regolith Explorer . Document the regolith at the sampling site at scales down to the sub-cm 1 OUR PAYLOAD PERFORMS EXTENSIVE CHARACTERIZATION AT GLOBAL AND SAMPLE-SITE-SPECIFIC SCALES SamCam images the sample site, documents sample OCAMS (UA) acquisition, and images TAGSAM to evaluate sampling success MapCam performs filter photometry, maps the surface, and images the sample site PolyCam acquires Bennu from >500K-km range, performs star- field OpNav, and performs high-resolution imaging of the surface OLA (CSA) provides ranging data out to 7 km and maps the asteroid shape and surface topography 2 OUR PAYLOAD PERFORMS EXTENSIVE CHARACTERIZATION AT GLOBAL AND SAMPLE-SITE-SPECIFIC SCALES OVIRS (GSFC) maps the reflectance albedo and spectral properties from 0.4 – 4.3 µm OTES (ASU) maps the thermal flux and spectral properties from 5 – 50 µm REXIS (MIT) trains the next generation of scientists and engineers and maps the elemental abundances of the asteroid surface Radio Science (CU) reveals the mass, gravity field, internal structure, and surface acceleration distribution 3 ASTEROID BENNU (1999 RQ36) IS WELL CHARACTERIZED • Size = 492-m (±20 m, mean diameter) • Shape = spheroidal “spinning top” • Rotation state = 4.3 hr period 4 ASTEROID BENNU (1999 RQ36) IS WELL CHARACTERIZED • Size = 492-m (±20 m, mean diameter) • Shape = spheroidal “spinning top” • Rotation state = 4.3 hr period What should types of spatial Infrastructure should a new planetary Mission develop so that we can better characterize Bennu using OSIRIS-REx? 5 COORDINATE SYSTEM PLAN • Refer to the IAU for coordinate system definition • For small bodies, we follow the right-hand rule for defining the positive pole • We have established a preliminary coordinate system • To define the origin of the coordinate system, we will begin with the COF and transition to the COM • We will define the Prime Meridian using a feature, and re-define the particular element of the feature is the PM higher Shape model of Bennu (Nolan) viewed from resolution images are acquired Small Body Mapping Tool 6 Coordinate System Definition Images generated by C. Johnson 7 Coordinate System Definition Approach PM Feature Images generated by C. Johnson 8 Coordinate System Definition Approach PM Feature Images generated by C. Johnson 9 Coordinate System Definition Approach PM Feature Preliminary Survey PM feature Images generated by C. Johnson 10 SMALL BODIES ARE…DIFFERENT • There are few standards for irregular bodies. • Small bodies are often irregularly shaped with regions that cannot be uniquely addressed using the longitude-latitude-radius system • A pure Cartesian system may be needed (see below) • There are few tools for data analysis or visualization that support 3D (x, y, z) for planetary bodies • Can we just make due with what is already out there? Shape model of 216 Kleopatra (Mitchell et al) viewed from Small Body Mapping Tool 11 But then we saw Comet 67P… Image from ESA Rosetta NavCam12 But then we saw Comet 67P… Image from ESA Rosetta NavCam Left: Optical Navigation Lead Coralie Jackman compares shape models of 67P Churyumov- Gerasimenko. On the left is a model derived from ground-based optical observations of the comet. The more complex and challenging shape Rosetta discovered is on the right. (Credit Coralie Jackman) 13 DATA ANALYSIS & VISUALIZATION 14 DATA ANALYSIS & VISUALIZATION ISIS3 15 DATA ANALYSIS & VISUALIZATION 16 SUMMARY • Think ahead about the who and what will unite your remotely-sensed data sets. • Small irregular bodies are different…ensure that existing tools are compatible, invest accordingly. • Where there exists few standards, set a good example. We are here! 17.
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