Integrated laboratory and electro-optical observational meteor studies

这项研究将结合实验室测量和使用“夜视”（图像增强器）和电荷耦合器件（CCD）数码相机的观察，研究流星如何在地球大气中消融和产生光。这项基于实验室的研究将使用脉冲激光使陨石的小区域蒸发。消融后产生的短时间光将使用同步数码相机、数字分光镜和光度计进行研究。扫描电子显微镜（SEM）将用于精确测量蒸发的陨石物质的质量。通过将这个质量与光和激光能量联系起来，我们将得到发光效率因子的估计。发光效率系数是产生的光与撞击大气分子的动能之比。由于大多数流星体的质量是通过整合流星产生的光并假设一个发光效率值来估计的，因此质量通量估计值以及相关的空间风险在很大程度上取决于这个值。我们将使用能量色散x射线光谱（EDS）来测量激光烧蚀前后元素的丰度。我们将确定流星是否以化学差异的方式消融，即更多的挥发性元素如钠或碳首先消融。据信，自46亿年前太阳系形成以来，来自彗星的流星体几乎没有改变。大多数流星体都是尘埃球，由一种挥发性更强的“胶水”聚集在一起，由数千个独立的尘埃颗粒组成。我们的微分消融工作将测试碳可能是这种“胶水”的前提。我们将使用带有CCD相机和光谱仪的望远镜光学来寻找尘埃碎片的证据。我们将继续探讨高速流星体的深度撞击对彗星核的污染问题。利用双望远镜、CCD探测器和光谱仪寻找流星体对月球的撞击，建立月球表面二次抛射对空间运行风险的模型。

The research will combine laboratory based measurements and observations using 'night vision' (image intensifiers) and charge coupled device (CCD) digital cameras to study how meteors ablate and produce light in the Earth's atmosphere. The laboratory based research will employ a pulsed laser to vaporize small regions of meteorites. The short duration light produced following ablation will be studied using synchronized digital cameras, digital spectroscopes and photometers. A scanning electron microscope (SEM) will be used to precisely measure the mass of meteorite material vaporized. By relating this mass to the light and laser energies, we will obtain an estimate of the luminous efficiency factor. The luminous efficiency factor is the ratio of the light produced to the kinetic energy of impinging atmospheric molecules. Since most meteoroid masses are estimated by integrating the light produced by the meteor and assuming a value for the luminous efficiency value, mass flux estimates, and the associated space risk, depends critically on this value. We will use energy dispersive X-ray spectroscopy (EDS) to measure the abundance of elements before and after laser ablation. We will determine if meteors ablate in a chemically differential manner, that is do more volatile elements such as sodium or carbon ablate first. Meteoroids from comets are believed to have been little altered since the formation of the solar system 4.6 billion years ago. Most meteoroids are dustballs, collections of thousands of individual dust grains held together by a more volatile 'glue'. Our differential ablation work will test the premise that carbon may be this 'glue'. We will use telescopic optics with the CCD cameras and spectrometers to search for evidence of dustball fragmentation. We will continue to explore this question of contamination of cometary nuclei by deep impact of high velocity meteoroids. We will use dual telescopes and CCD detectors and spectrometers in order to search for meteoroid impacts on the moon, and develop models for the risk of secondary ejecta to space operations on the surface of the moon.