RUI: Radar Studies of Carbonaceous Mainbelt Asteroids

Christopher Magri AST 9973216这个观测项目将利用波多黎各阿雷西博天文台新升级的雷达系统来研究碳质主带小行星（mba）。碳质小行星被认为与外层太阳星云中凝结的原始固体相对没有变化。最外层的小行星表面可能有复杂的有机分子。雷达导出的数据将用于设定目标形状、地形、旋转状态、成分和近表面粗糙度的约束条件，以定义包含暗天体的各种分类类别之间以及碳质mba与其他小行星之间的异同。该项目是最近在阿雷西博升级之前雷达检测到的所有mba的统计分析的逻辑结果。许多小行星目标将在中等信噪比下使用多普勒（连续波）技术进行探测。这些首次检测将用于在每个碳质分类类别中建立数据样本。较少数量的目标将产生具有足够高信噪比的回波，从而可以有效地利用时间分辨信号。根据到达时间和频率对回声进行分频后得到的“延迟多普勒”图像将被用作形状建模分析的输入。对于信噪比接近100的数据集，分析将产生目标极点轮廓的约束，并且对于信噪比值为数百的数据集，也可以涉及三维形状重建。将要使用的软件工具将包括商业软件包和由喷气推进实验室的一个研究小组开发的雷达专用程序。

Abstract - Christopher Magri AST 9973216This observational program will make use of the newly upgraded radar system at the Arecibo Observatory in Puerto Rico to study carbonaceous mainbelt asteroids (MBAs). Carbonaceous asteroids are thought to be relatively unaltered from the primordial solids that condensed in the outer solar nebula. The outermost asteroids probably have complex organic molecules on their surfaces. The radar-derived data will be used to set constraints on target shape, topography, rotation state, composition, and near-surface roughness to define similarities and differences between the various taxonomic classes containing dark objects and between carbonaceous MBAs and other asteroids. The project is a logical outgrowth of recent statistical analysis of all MBAs detected by radar prior to the Arecibo upgrade. Many asteroid targets will be detected at moderate signal-to-noise ratio (SNR) using Doppler-only (continuous wave) techniques. These first-time detections will be used to build up data samples within each of the carbonaceous taxonomic classes. A smaller number of targets will produce echoes with high enough SNR that time-resolved signals can profitably be utilized. The "delay-Doppler" images that result from binning the echo, both by arrival time and by frequency, will be used as the input to shape-modeling analyses. The analyses will yield constraints on the target's pole-on silhouette for datasets with SNR approaching 100, and can also involve three-dimensional shape reconstruction for SNR values of several hundreds. The software tools to be used will include both commercial packages and radar-specific programs developed by a research group at the Jet Propulsion Laboratory.