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I. Report on Research Activities I Was Selected As a Participating Scientist

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I. Report on Research Activities I Was Selected As a Participating Scientist I. Report on research activities I was selected as a Participating Scientist on the Hayabusa2 mission in 2016. I started working in collaboration with the camera (ONC) team. I also took advantage oF the opposition oF Ryugu during the summer to take some IRTF spectra. I reduced it using Spextools and presented the first results during the Hayabusa2 science team meeting at JAXA in Tokyo. In addition, I presented to the Hayabusa2 team the work I intend to do using the multi-band camera and how I will support the team For the selection oF the sampling site. I am a Co-Investigator in a PMDAP grant dedicated to calibrate and archive data From the First Hayabusa mission. The Focus this year has been to complete all the necessary soFtware development, mainly in ISIS, to prepare For systematic processing oF the AMICA images. The processing will apply ingestion (amica2isis), updates to AMICA timing (there is known uncertainty oF 12 seconds For the start observation time corrected with Gaskell SUMFILE data using sumspice), radiometric calibration (amicacal), apply SPICE ephemeris, adjust control using Gaskell SUMFILE data (sumspice), project individual images (cam2map) and create global mosaics. The application amicacal also includes an option to remove the pixels corresponding to the polarizing Filters on the leFt side oF the image Frame. We have a working version oF amicacal For radiometric calibration oF AMICA images. sumspice was developed to apply ephemeris pointing and spacecraFt position data to individual images using Gaskell SUMFILEs, a byproduct oF digital elevation modeling (DEM) processes. It has been designed to also apply timing corrections contained within the SUMFILEs to image observation start times. Testing oF this application as applied to AMICA images oF Itokawa shows very good alignment aFter application oF timing, pointing and spacecraFt position updates. We presented our results on this work and the First preliminary global maps oF Itokawa in color at the DPS meeting in Pasadena. For Hayabusa NIRS (spectrometer) data processing, I tested my IDL code that makes use oF SPICE routine to derive the geometry oF the NIRS Footprints with a low resolution and high resolution Itokawa shape model available as a DSK From the PDS/NAIF website. I extracted coordinates and viewing geometry For the center and four corners of all the NIRS footprints. I wrote several IDL scripts for extracting the geometry From the PDS data and getting our results in tables, and I also created lists to compare latitudes, longitudes and geometry For the whole NIRS dataset. I modiFied my initial IDL script to be able to extract each shape model plate that is visible within the FOV of NIRS and extract centroid coordinates and viewing geometry. My code uses the latest version oF routines written by the JPL NAIF team in the Alpha DSK toolkit, preliminary version oF the SPICE toolkit N66. I continue my work on image processing For the OSIRIS-REx mission. I implemented a pipeline For the creation oF Mapcam and Polycam image mosaics. This processing pipeline can sort the images by Filter and apply several tests on the data. The input images in I/F can be trimmed according to incidence and emission angles and are reprojected individually beFore creating a mosaic. DiFFerent projections are then created. Pointing and trajectory inFormation For each image can be updated to produce controlled mosaics with image registered to the shape model of Bennu with high precision. For the color mosaics, interesting parameters For the study of space weathering and surface composition were implemented such as ratios and equation for the 0.7 µm absorption band depth. All data products are exported to png maps and gridded maps as well as ENVI compatible Formats. I am the Principal Investigator oF a PMDAP grant dedicated to calibrate and archive Framing Camera data From the Vesta phase oF the Dawn mission (mostly using HAMO data). This year I prepared all the scripts to process image mosaics and test the quality oF the registration oF each image in a mosaic. I create a HAMO color mosaic with SPICE kernels available online. The next step will be to compare this map with the controlled mosaic that I will produce using Gaskell’s SUMFILES. Finally, I was part oF two proposals submitted to the program Planetary Science Deep Space SmallSat Studies. I am a Collaborator on Driss Takir (SETI) proposal “Asteroid Reconnaissance For Researching Organics and Water in the Solar System (ARROWS^2)” which is a mission to visit three to eight primitive asteroids with one to three small spacecrafts. The ARROWS2 mission will (1) investigate the abundance and distribution oF water and organics in the inner and outer main asteroid belt (0.5 < a < 5 AU), (2) test the current thermal and dynamical models For the origin and evolution oF primitive bodies, and (3) place the returned pristine and primitive samples From NASA’s OSIRIS-REx and JAXA’s Hayabusa2 sample return missions in context with the larger asteroid population. I am also a Co-Investigator on Ralph Harvey (Case Western Reserve University) proposal “DAISEE: Diminutive Asteroid In Situ Evolution Explorer” which is a mission to rendezvous and orbit a small (5-20 m) Near-Earth Object (NEO). DAISEE builds on a predecessor mission concept (the DAVID mission chosen For technology development within the SIMPLEX-1 program) but provides greatly enhanced science within the reduced constraints oF the Deep Space SmallSat program. II. Publications Peer-Reviewed 1. A. Nathues, M. HoFFmann, T. Platz, G.S. Thangjam, E.A. Cloutis, V. Reddy, L. Le Corre, J.-Y. Li, K. Mengel, A. Rivkin, D.M. Applin, M. SchaeFer, U. Christensen, H. Sierks, J. Ripken, B.E. Schmidt, H. Hiesinger, M.V. Sykes, H.G. Sizemore, F. Preusker, C.T. Russell, FC colour images oF dwarF planet Ceres reveal a complicated geological history, Planetary and Space Science, Volume 134, 1 December 2016, Pages 122-127, ISSN 0032-0633, http://dx.doi.org/10.1016/j.pss.2016.10.017. 2. Reddy, V., Sanchez, J.A., Bottke, W.F., Thirouin, A., Rivera-Valentin, E.G., Kelley, M.S., Ryan, W., Cloutis, E.A., Tegler, S.C., Ryan, E.V., Taylor, P.A., Richardson, J.E., Moskovitz, N., Le Corre, L., Physical Characterization of ~2 M Diameter Near-Earth Asteroid 2015 TC25: A Possible Boulder From E-type Asteroid (44) Nysa. The Astronomical Journal, Volume 152, Issue 6, article id. 162, 7 pp. (2016). 3. David T. Blewett, Brett W. Denevi, Lucille Le Corre, Vishnu Reddy, Stefan E. Schröder, Carle M. Pieters, Federico Tosi, Francesca Zambon, Maria Cristina De Sanctis, Eleonora Ammannito, Thomas Roatsch, Carol A. Raymond, Christopher T. Russell, Optical space weathering on Vesta: Radiative-transFer models and Dawn observations, Icarus, Volume 265, February 2016, Pages 161-174, ISSN 0019-1035, http://dx.doi.org/10.1016/j.icarus.2015.10.012. 4. Li, Jian-Yang; Reddy, Vishnu; Nathues, Andreas; Le Corre, Lucille; Izawa, Matthew R. M.; Cloutis, Edward A.; Sykes, Mark V.; Carsenty, Uri; Castillo- Rogez, Julie C.; HoFFmann, Martin; Jaumann, RalF; Krohn, Katrin; Mottola, SteFano; Prettyman, Thomas H.; SchaeFer, Michael; Schenk, Paul; Schröder, SteFan E.; Williams, David A.; Smith, David E.; Zuber, Maria T.; Konopliv, Alexander S.; Park, Ryan S.; Raymond, Carol A.; Russell, Christopher T., SurFace Albedo and Spectral Variability oF Ceres. The Astrophysical Journal Letters, Volume 817, Issue 2, article id. L22, 7 pp. (2016). Abstracts 1. Le Corre, Lucille; Becker, Kris J.; Reddy, Vishnu; Li, Jian-Yang; Bhatt, Megha, Mineralogical Mapping oF Asteroid Itokawa using Calibrated Hayabusa AMICA images and NIRS Spectrometer Data. American Astronomical Society, DPS meeting #48, id.325.09, 2016. 2. Li, Jian-Yang; Le Corre, Lucille; Reddy, Vishnu; Nathues, Andreas; HoFFmann, Martin; SchaeFer, Michael; Ciarniello, Mauro; Mottola, SteFano; Schröder, SteFan E.; Raymond, Carol A.; Russell, Christopher T., Spectrophotometric Modeling and Mapping oF Ceres. EGU General Assembly 2016, held 17-22 April, 2016 in Vienna Austria, p.17302 3. Li, J.-Y.; Le Corre, L.; Reddy, V.; Nathues, A.; HoFFmann, M.; SchaeFer, M.; Ciarniello, M.; Mottola, S.; Schröder, S. E.; Raymond, C. A.; Russell, C. T., Spectrophotometric Modeling and Mapping oF Ceres. 47th Lunar and Planetary Science Conference, held March 21-25, 2016 at The Woodlands, Texas. LPI Contribution No. 1903, p.2095 4. Schenk, P.; Marchi, S.; O'Brien, D.; Bland, M.; Platz, T.; Hoogenboom, T.; Kramer, G.; Schroeder, S.; De Sanctis, M.; Buczkowski, D.; Sykes, M.; McFadden, L.; Ruesch, O.; Le Corre, L.; Schmidt, B.; Hughson, K.; Russell, C. T.; Scully, J.; Raymond, C., Impact Cratering on the Small Planets Ceres and Vesta: S-C Transitions, Central Pits, and the Origin of Bright Spots. 47th Lunar and Planetary Science Conference, held March 21-25, 2016 at The Woodlands, Texas. LPI Contribution No. 1903, p.2697 5. DellaGiustina, D. N.; Barnouin, O. S.; Nolan, M. C.; Johnson, C. A.; Le Corre, L.; Lauretta, D. S., Cartographic Planning for the OSIRIS-REx Asteroid Sample Return Mission. 47th Lunar and Planetary Science Conference, held March 21-25, 2016 at The Woodlands, Texas. LPI Contribution No. 1903, p.1668 III. Awards and Honors None IV. Service to the Science Community (e.g., advisory panels, society oFFices) - Served on R&A and PDS Review panels - Reviewer for Icarus V. Public outreach activities Visit to Sierra Vista astronomy club Several interviews by journalists .
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