کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1782211 1523973 2007 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Comparison of the dust distributions in the innermost comae of comets-1P/Halley and 19P/Borrelly spacecraft observations
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فیزیک زمین (ژئو فیزیک)
پیش نمایش صفحه اول مقاله
Comparison of the dust distributions in the innermost comae of comets-1P/Halley and 19P/Borrelly spacecraft observations
چکیده انگلیسی
We present a comparative study of the inner comae of comets 1P/Halley and 19P/Borrelly using data from the Halley Multicolour Camera (HMC) onboard Giotto and the Miniature Integrated Camera and Spectrometer onboard Deep Space 1 (DS1). We show that the dust brightness dependence as a function of radial distance is different for both comets. We suggest that optical depth or fragmentation effects dominate the brightness distribution at comet 1P/Halley whereas acceleration or non-point source geometry effects dominate at comet 19P/Borrelly. The nightside profiles of comet 19P/Borrelly suggest a continuing non-radial outflow from the nucleus out to several tens of kilometres. This modifies the observed dayside to nightside brightness ratio with distance and offers a further constraint on dust emission models. By setting up a linear system of equations to fit the dust intensity distribution, better fits could be obtained by incorporating acceleration into the equation of free-radial outflow. Finally, we estimate the dust production rate of 19P/Borrelly at the time of DS1 encounter as no higher than 324 kg/s based on comparisons with HMC intensity measurements.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Planetary and Space Science - Volume 55, Issues 7–8, May 2007, Pages 974-985
نویسندگان
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