The original proposal was titled "Analysis of polar processes for the Mars Odyssey THEMIS investigation". There were two main topics in this investigation: analysis of evolution of the seasonal ice cap and analysis of off-nadir and stereo opportunities. Main goal of the first topic is to establish a long term observation procedure for the retreat of the seasonal ice caps on Mars. This year's progress builds on previous work (Ivanov, 2005), which established the algorithm and provided first data on the retreat of the seasonal ice cap in the Northern hemisphere. This year analysis was expanded to the recent THEMIS data. Analysis is being done for both North and South Hemispheres. Results of this work will be presented at LPSC conference in March 2008 (Ivanov, 2008). The second topic was to analyze feasibility of using THEMIS data for stereo observations to derive terrain topography. While there is some use of nadir THEMIS images to observe high altitude cloud phenomena, topography observations required pointing of the spacecraft into off-nadir configuration. Unfortunately, it was not possible to perform these observations on a regular basis. Analysis of stereo pairs using THEMIS and MOC high resolution data did not yield considerable output and therefore this project is now discontinued.
Dr. Ivanov's primary responsibility is maintenance of the MARSIS data processing pipeline at JPL. In addition to the standard data processing, there are extra data products that are being produced. Standard MARSIS data is processed and compressed onboard of the spacecraft. MARSIS instrument has a special mode when data is not compressed and transmitted directly to the ground allowing for a better along the track resolution at a cost of less coverage. This data is also known as "flash data" as it is written into a flash memory inside the MARSIS instrument. Changes in processing and available geometry data also required reprocessing of the data. MARSIS data processed at JPL and corresponding browse products have been used intensively for science analysis and publications.
[1] A. Safaeinili, W. Kofman, J. Mouginot, Y. Gim, A. Herique, A. B. Ivanov, J. J. Plaut, and G. Picardi. Estimation of the total electron content of the Martian ionosphere using radar sounder surface echoes. GRL, 34:23204-+, December 2007.
[2] J. J. Plaut, G. Picardi, A. Safaeinili, A. B. Ivanov, S. M. Milkovich, A. Cicchetti, W. Kofman, J. Mouginot, W. M. Farrell, R. J. Phillips, S. M. Clifford, A. Frigeri, R. Orosei, C. Federico, I. P. Williams, D. A. Gurnett, E. Nielsen, T. Hagfors, E. Heggy, E. R. Stofan, D. Plettemeier, T. R. Watters, C. J. Leuschen, and P. Edenhofer. Subsurface Radar Sounding of the South Polar Layered Deposits of Mars. Science, 316:92-, April 2007.
[3] T. R. Watters, B. Campbell, L.Carter, C. J. Leuschen, J. J. Plaut, G. Picardi, R. Orosei, A. Safaeinili, S. M. Clifford, W. M. Farrell, A. B. Ivanov, R. J. Phillips, and E. R. Stofan. Radar Sounding of the Medusae Fossae Formation Mars: Equatorial Ice or Dry, Low-Density Deposits? Science, 318(5853):1125-1128, 2007.
[4] J. J. Plaut, A. Ivanov, A. Safaeinili, S. M. Milkovich, G. Picardi, R. Seu, and R. Phillips. Radar Sounding of Subsurface Layers in the South Polar Plains of Mars: Correlation with the Dorsa Argentea Formation. In Lunar and Planetary Institute Conference Abstracts, volume 38 of Lunar and Planetary Institute Conference Abstracts, pages 2144-+, March 2007.
[5] T. R. Watters, B. A. Campbell, L. M. Carter, C. J. Leuschen, J. J. Plaut, G. Picardi, A. Safaeinili, S. M. Clifford, W. M. Farrell, A. B. Ivanov, R. J. Phillips, E. R. Stofan, and Marsis Science Team. MARSIS Subsurface Radar Sounding of the Medusae Fossae Formation, Mars. In Lunar and Planetary Institute Conference Abstracts, volume 38 of Lunar and Planetary Institute Conference Abstracts, pages 1661-+, March 2007.