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

木星特洛伊木马的碰撞碎片是了解太阳系形成的窗口

• 批准号: 2109212
• 负责人: Michael Brown
• 金额: $ 35.84万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2109212&HistoricalAwards=false
• 关键词: Collisional; fragments; Jupiter; Trojans; windows

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.

加州理工学院开展的这一项目旨在解决木星特洛伊小行星的起源问题，木星特洛伊小行星是木星轨道上的小行星群，这两个星团位于轨道上的重力稳定点，一个在木星前面，另一个在木星后面。这些小行星的起源仍然未知，该项目旨在检查最近经历过碰撞的木星特洛伊木马的组成，以深入了解它们的历史。该项目的更广泛影响包括对 Coursera 上名为“太阳系科学”的免费在线课程的重大升级。升级将包括最后 5 个课程。多年的太空探索并基于对太阳系早期动力学历史的研究开发了新的丰富内容木星特洛伊木马的组成为太阳系的动力学历史提供了关键的观测线索，但人们对这些物体的成分知之甚少，因为长期的照射和连续的粒子轰击已将它们的表面变成了黑暗的难熔沉积物，没有可识别的光谱特征，这个多面项目将研究木星特洛伊小行星最近的碰撞碎片。具有新暴露的内部材料的碎片将有助于深入了解它们的组成、形成历史以及早期太阳系动态演化的本质，将对尺寸约为 5 的物体进行系统研究。 km，其中所有物体都应该持续发生碰撞，最多大约 40 km，其中只有偶尔的物体应该经历过最近的碰撞，使用 Palomar 可见光度测量、Keck 红外光谱和 ALMA 辐射测量的组合，计算反照率、成分和辐射。这项研究将研究这些碎片的碰撞历史，揭示这些物体的起源、它们与小行星主带或柯伊伯带的联系，以及早期的动力学历史。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

An ALMA Search for High-albedo Objects Among the Midsized Jupiter Trojan Population

ALMA 在中型木星特洛伊群中寻找高反照率天体

• DOI: 10.3847/1538-3881/ac559e
• 发表时间: 2022-02-14
• 期刊: The Astronomical Journal
• 作者: Anna M. Simpson;M. Brown;M. Schemel;B. Butler
• 通讯作者: B. Butler