Supernova 1987A: Versatile Astrophysical Tool & Unique Opportunity to Study SNR Formation

超新星1987 A是近四个世纪以来观测到的距离最近的超新星，也是研究最深入的一颗，随着爆炸的喷出物撞击到这颗星星在过去一百万年里脱落的星周包层上，它正在迅速变成超新星遗迹。在本项目中，将结合使用档案、光学、红外线和紫外线方案以及空间研究来跟踪这一进程。克罗茨博士先前对三维结构、速度、密度和成分的观察将确定爆炸前星云的性质以及产生它的质量损失过程，而对碰撞中产生的X射线和极紫外线通量对该星云的激发的新观察将使克罗茨博士能够再次重新分析它。除了这次对超新星遗迹的研究，克罗茨博士还将继续利用超新星爆炸的光回波来探索剑鱼座30恒星形成区的星际介质，研究超新星冲击爆发的紫外线脉冲通过祖星星表面的回波，并精确地确定到大麦哲伦云的距离--这是河外距离阶梯上的一个基本梯级。克罗茨博士还将探索他的图像差分软件在生物医学成像中的应用-特别是用于跟踪超新星回波外观变化的图像处理算法如何跟踪其他数据集的变化，特别是用于早期检测癌症生长的CT扫描染料测试。光回波数据还将用于渲染和动画，作为光回波揭示的迷人结构的几个公共访问演示的一部分。

Supernova 1987A, the closest supernova seen in nearly four centuries, and the most intensely studied, is rapidly turning into a supernova remnant as the ejecta from the explosion now strikes the circumstellar envelope shed by the star over the last million years. In this project, this process will be followed using a combination of archival, optical, infra-red and ultra-violet programs, plus space-based studies. Previous observations taken by Dr. Crotts of the three dimensional structure, velocities, density and composition will establish the nature of the pre-explosion nebula and the mass loss processes that created it, while new observations of the excitation of this nebula by the X-ray and extreme ultra-violet flux created in the collision will enable Dr. Crotts to re-analyze it once more. In addition to this study of a supernova remnant, Dr. Crotts will continue to use light echoes from the supernova explosion to explore the interstellar medium in the 30 Doradus star-formation region, to study the echo of the ultra-violet pulse from supernova shock breakout through the progenitor star's surface, and accurately to determine the distance to the Large Magellanic Cloud - a fundamental rung on the extragalactic distance ladder. Dr. Crotts will also explore the application of his image differencing software to biomedical imaging - specifically how the image processing algorithms used to trace changes in the appearance of supernova echoes can track changes in other data sets, prominently CT-scan dye tests used for early detection of cancerous growths. The light echo data will also be used in renderings and animations as part of several public-access demonstrations of the fascinating structures revealed by light echoes.