Collaborative Research: Tidal disruption of near-Earth asteroids

合作研究：近地小行星的潮汐破坏

• 批准号: 2108440
• 负责人: Kevin Walsh
• 金额: $ 29.55万
• 依托单位: Southwest Research Institute
• 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: 2021-10-01 至 2024-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2108440&HistoricalAwards=false
• 关键词: Collaborative; Research; Tidal; disruption; near

This collaborative project between Southwest Research Institute and the University of Maryland College Park studies how gravitational forces can reshape or tear apart near-Earth asteroids (NEAs). “Rubble-pile” asteroids (which are loose collections of material) and comets are known to reshape or come apart, through a process known as tidal distortion and disruption, as they pass close to planets. This research team will use computer simulations with inputs from observations to examine how tidal disruption changes the population of NEAs. They will address topics such as how many fragments are created, what their orbits are, and how many odd shapes can be attributed to the process. This will provide important insight into their history and potential futures and has relevance to planetary defense. The broader impacts leverage the interest of the general public in NEAs to continue a long-running public outreach program and to build an accessible toolset and lesson plan for wide use.Near-Earth asteroids are some of the closest and therefore best-studied objects in the Solar System, yet it is not known how pervasive the effects of tidal disruption could be among NEAs. This research team will model the interaction of rubble-pile asteroids having close flybys of terrestrial planets. They will determine whether their soft-sphere discrete code can produce some of the irregularly shaped NEAs, re-process their surfaces, and alter the size and orbital distribution of near-Earth asteroids. Through accurate modeling of the surface interactions between particles, this group will capture the effect of frictional forces and irregular shaped constituent pieces for a complete suite of tidal disruption models. Testing over the entire range of possible encounter scenarios (close approach and velocity) for the terrestrial planets, including a range of spin states (spin axis orientation and spin rates) and internal structure (large interior blocks), will be used to create a catalog of outcomes necessary to estimate how widely this process has altered the near-Earth population and be able to estimate the bodies most likely to have been affected.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.

西南研究所和马里兰州大学帕克分校之间的这个合作项目研究了引力如何重塑或撕裂近地小行星（NEAs）。 众所周知，“碎石堆”小行星（松散的物质集合）和彗星在靠近行星时会通过一种称为潮汐扭曲和破坏的过程重塑或分裂。该研究小组将使用计算机模拟，并从观测中获得输入，以研究潮汐扰动如何改变近地小行星的数量。他们将讨论的主题，如有多少碎片被创建，它们的轨道是什么，以及有多少奇怪的形状可以归因于这个过程。这将为他们的历史和潜在的未来提供重要的洞察力，并与行星防御有关。更广泛的影响利用了公众对近地小行星的兴趣，以继续开展长期的公众宣传方案，并建立一套便于使用的工具和课程计划供广泛使用。近地小行星是太阳系中距离最近的天体之一，因此也是研究得最好的天体，但目前还不知道潮汐扰动的影响在近地小行星中有多普遍。这个研究小组将模拟碎石堆小行星与类地行星近距离飞越的相互作用。 他们将确定其软球离散代码是否能够产生一些形状不规则的近地小行星，对其表面进行再处理，并改变近地小行星的大小和轨道分布。通过对颗粒之间的表面相互作用进行精确建模，该小组将捕获摩擦力和不规则形状的组成部分的影响，以建立一套完整的潮汐破坏模型。在整个可能遭遇场景范围内进行测试（近距离接近和速度）的类地行星，包括一系列的自旋状态（自旋轴取向和自旋速率）和内部结构（大型内部街区），将被用来创建一个必要的结果目录，以估计这一过程在多大程度上改变了近-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。