Collisional fragments of Jupiter Trojans as windows into the formation of the solar system

这个项目在加州理工学院进行，旨在解决木星特洛伊的起源，这是木星轨道上的小行星群。这两个星团位于轨道上引力稳定的点，一个在行星的前面，另一个在行星的后面。这些小行星的起源仍然未知。该项目旨在研究最近发生碰撞的木星特洛伊人的组成，以了解他们的历史。将使用来自几个地面观测站的数据对暴露的材料进行检查，这些地面观测站包括凯克观测站和阿塔卡马大型毫米/亚毫米阵列（阿尔马）。该项目的更广泛影响包括对Coursera上的免费在线课程进行重大升级，称为太阳系科学。升级将包括过去5年的太空探索，并在研究太阳系早期动力学历史的基础上开发新的丰富内容。木星特洛伊的组成为太阳系的动力学历史提供了重要的观测线索，但对这些天体的组成知之甚少，因为长期的照射和连续的粒子轰击使它们的表面变成了黑暗的耐火沉积物，没有可识别的光谱特征。这个多方面的项目将研究木星特洛伊小行星最近的碰撞碎片。观察最近的碎片与新鲜暴露的内部材料将提供深入了解他们的组成，他们的形成历史，以及早期太阳系的动态演化的性质。将对大小从约5公里到约40公里的物体进行系统研究，在约5公里处，所有物体都应具有持续的碰撞活性，在约40公里处，只有偶尔的物体应经历过最近的碰撞。将结合使用Palomar可见光光度测定法、Keck红外光谱法和阿尔马辐射测定法，对这些碎片的丰度、成分和碰撞历史进行研究。这项研究将揭示这些天体的起源，它们与小行星主带或柯伊伯带的联系，以及早期太阳系的动力学历史。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project carried out at the California Institute of Technology seeks to address the origin of Jupiter Trojans, which are clusters of asteroids in Jupiter’s orbit. These two clusters sit at gravitationally stable points in the orbit, one ahead of the planet, and the other behind. The origin of these asteroids is still unknown. This project is to examine the composition of the Jupiter Trojans that have recently undergone collisions to obtain insight into their history. The exposed material will be examined using data from several ground-based observatories including the Keck Observatory and the Atacama Large Millimeter/submillimeter Array (ALMA). The broader impacts of this project include significant upgrades to a free online class available on Coursera called The Science of the Solar System. The upgrades are to include the last 5 years of space exploration and to develop new rich content based on the research into the early dynamical history of the solar system. The composition of the Jupiter Trojans provides a critical observational clue into the dynamical history of the solar system, but little is known about the compositions of these objects, because long term irradiation and continuous particle bombardment have turned their surfaces into dark refractory deposits with no identifiable spectral features. This multi-faceted project will study recent collisional fragments of Jupiter Trojan asteroids. Observing recent fragments with freshly exposed interior materials will provide insight into their composition, into their formation history, and the nature of the dynamical evolution of the early solar system. A systematic study will be carried out of objects in size from approximately 5 km, where all objects should be continuously collisionally active, up to approximately 40 km, where only the occasional object should have experienced a recent collision. Using combinations of Palomar visible photometry, Keck infrared spectroscopy, and ALMA radiometry, the albedo, composition, and collisional history of these fragments will be examined. This study will reveal the origin of these objects, their connection to the main belt of asteroids or to the Kuiper belt, and, by extension, the dynamical history of the early solar system.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.