کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8143089 1523923 2015 4 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
New Ganymede control point network and global shape model
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فیزیک زمین (ژئو فیزیک)
پیش نمایش صفحه اول مقاله
New Ganymede control point network and global shape model
چکیده انگلیسی
We computed a 3D control point network for Ganymede using combinations of 126 Voyager-1 and -2 and 87 Galileo images, benefiting from reconstructed trajectory data for the three spacecraft and a more complete Galileo image data base than was available for earlier studies. Using more than 3000 control point coordinates, we determine global shape parameters, including mean radius, spheroid- and ellipsoidal axes, and make tests for various equilibrium shape models, constrained by the most recent estimates for gravity field parameters. We confirm that Ganymede has a pronounced ellipsoidal shape, approximately aligned with the Jupiter-direction, in agreement with Ganymede being in tidal equilibrium. The point heights, suffering from large individual errors, do not reveal any large-scale topography below our typical error levels (97% <5 km). By analysis of data residuals we search for, but cannot detect Ganymede longitudinal forced librations. We conclude that libration amplitudes cannot be larger than 0.1° (corresponding to a lateral displacement of 4.6 km at the equator).
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Planetary and Space Science - Volume 117, November 2015, Pages 246-249
نویسندگان
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