Time variations of Mars' gravitational field and seasonal changes in the masses of the polar ice caps
Tracking of the Mars Global Surveyor spacecraft has been used to measure changes in the long-wavelength gravity field of Mars and to estimate the seasonal mass of carbon dioxide that is deposited in the polar regions each fall and winter and sublimed back into the atmosphere every spring and summer....
| Автори: | , , , , , , |
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| Формат: | Стаття |
| Мова: | en_US |
| Опубліковано: |
American Geophysical Union
2012
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| Онлайн доступ: | http://hdl.handle.net/1721.1/74244 https://orcid.org/0000-0003-2652-8017 |
| _version_ | 1826200909214908416 |
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| author | Smith, David E. Zuber, Maria Torrence, Mark H. Dunn, Peter J. Neumann, Gregory A. Lemoine, Frank G. Fricke, Susan K. |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Smith, David E. Zuber, Maria Torrence, Mark H. Dunn, Peter J. Neumann, Gregory A. Lemoine, Frank G. Fricke, Susan K. |
| author_sort | Smith, David E. |
| collection | MIT |
| description | Tracking of the Mars Global Surveyor spacecraft has been used to measure changes in the long-wavelength gravity field of Mars and to estimate the seasonal mass of carbon dioxide that is deposited in the polar regions each fall and winter and sublimed back into the atmosphere every spring and summer. Observations spanning 4 Mars years have been analyzed. A clear and well-defined seasonal signal, composed of annual and semiannual periods, is seen in the lowest odd degree 3 coefficient but with less confidence in the lowest even degree 2, which is expected to be smaller and is also much more difficult to observe. Direct estimation of the seasonal mass exchange employing a simple, seasonally varying model of the size and height of each cap provides values that indicate some systematic departures from the deposition predicted by a general circulation model. Estimates are also obtained for the precession and nutation of the pole of rotation of Mars, the degree 2 tidal Love number, k 2, and the mass of Phobos, the larger of Mars' two natural satellites. |
| first_indexed | 2024-09-23T11:43:36Z |
| format | Article |
| id | mit-1721.1/74244 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T11:43:36Z |
| publishDate | 2012 |
| publisher | American Geophysical Union |
| record_format | dspace |
| spelling | mit-1721.1/742442022-10-01T05:33:04Z Time variations of Mars' gravitational field and seasonal changes in the masses of the polar ice caps Smith, David E. Zuber, Maria Torrence, Mark H. Dunn, Peter J. Neumann, Gregory A. Lemoine, Frank G. Fricke, Susan K. Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Zuber, Maria Tracking of the Mars Global Surveyor spacecraft has been used to measure changes in the long-wavelength gravity field of Mars and to estimate the seasonal mass of carbon dioxide that is deposited in the polar regions each fall and winter and sublimed back into the atmosphere every spring and summer. Observations spanning 4 Mars years have been analyzed. A clear and well-defined seasonal signal, composed of annual and semiannual periods, is seen in the lowest odd degree 3 coefficient but with less confidence in the lowest even degree 2, which is expected to be smaller and is also much more difficult to observe. Direct estimation of the seasonal mass exchange employing a simple, seasonally varying model of the size and height of each cap provides values that indicate some systematic departures from the deposition predicted by a general circulation model. Estimates are also obtained for the precession and nutation of the pole of rotation of Mars, the degree 2 tidal Love number, k 2, and the mass of Phobos, the larger of Mars' two natural satellites. United States. National Aeronautics and Space Administration (Mars Global Surveyor Project, NASA Mars Program) 2012-10-24T19:49:55Z 2012-10-24T19:49:55Z 2009-05 2008-12 Article http://purl.org/eprint/type/JournalArticle 0148-0227 2156–2202 http://hdl.handle.net/1721.1/74244 Smith, David E. et al. “Time Variations of Mars’ Gravitational Field and Seasonal Changes in the Masses of the Polar Ice Caps.” Journal of Geophysical Research 114.E5 (2009): E05002. Web. ©2009 American Geophysical Union. https://orcid.org/0000-0003-2652-8017 en_US http://dx.doi.org/10.1029/2008je003267 Journal of Geophysical Research. Planets Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Geophysical Union MIT web domain |
| spellingShingle | Smith, David E. Zuber, Maria Torrence, Mark H. Dunn, Peter J. Neumann, Gregory A. Lemoine, Frank G. Fricke, Susan K. Time variations of Mars' gravitational field and seasonal changes in the masses of the polar ice caps |
| title | Time variations of Mars' gravitational field and seasonal changes in the masses of the polar ice caps |
| title_full | Time variations of Mars' gravitational field and seasonal changes in the masses of the polar ice caps |
| title_fullStr | Time variations of Mars' gravitational field and seasonal changes in the masses of the polar ice caps |
| title_full_unstemmed | Time variations of Mars' gravitational field and seasonal changes in the masses of the polar ice caps |
| title_short | Time variations of Mars' gravitational field and seasonal changes in the masses of the polar ice caps |
| title_sort | time variations of mars gravitational field and seasonal changes in the masses of the polar ice caps |
| url | http://hdl.handle.net/1721.1/74244 https://orcid.org/0000-0003-2652-8017 |
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