The Astrophysics of Near-Earth Supernova Explosions

超新星爆炸在宇宙学、天体物理学和基本粒子物理学中起着核心作用。现在有确凿的实验证据表明，在过去的几百万年里，在距离地球300光年的范围内至少发生过一次超新星爆炸。这些证据来自对广泛存在的深海样本中短寿放射性同位素铁-60的测量，以及对月球风化层和宇宙射线的测量。这是第一个确定的太阳系外特定日期的天体物理事件对地球产生可测量影响的例子。伊利诺伊大学的一个研究小组将解释这些数据，因为他们系统地发展了这个新领域的天体物理学。它的意义跨越了天体物理学和其他领域，包括本地超新星和恒星形成率，太阳本地环境的性质和历史，宇宙射线天体物理学，甚至古生物学和生物大灭绝。科学家们还致力于通过多种形式的公众宣传将他们的科学带给公众。这项研究将包括一项理论研究，以(1)确定超新星距离和时代的允许范围，(2)研究超新星的质量、核合成和尘埃形成特性，以及(3)为磁化介质中带电超新星尘埃的传播、演化和生存建立模型，以了解观测到的超新星碎片沉降的持续时间。这些结果将对超新星爆炸模型、超新星残骸和高红移星系中的尘埃产生产生影响。推广活动将包括三个方面的努力：(1)将天文学和天体物理学带给当地州立监狱的大学生，用研究来激发讨论和兴趣。(2)利用2024年4月8日的日食为契机，向公众介绍天文学和天体物理学，并说明宇宙如何以通常难以察觉但有时戏剧性的方式干预我们的生活；(3)在校园、学校、教堂和社区团体中频繁进行公开演讲。该奖项反映了美国国家科学基金会的法定使命，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。

Supernova explosions play a central role in cosmology, astrophysics, and elementary particle physics. There is now solid experimental evidence of at least one supernova explosion within 300 light years of Earth within the last few million years, from measurements of the short-lived radioisotope iron-60 in widespread deep-ocean samples, as well as in the lunar regolith and in cosmic rays. This is the first established example of a specific dated astrophysical event outside the Solar System having a measurable impact on the Earth. A research group at the University of Illinois will interpret these data as they systematically develop the astrophysics of this new field. The implications span much of astrophysics and beyond, informing topics including local supernova and star formation rates, the nature and history of the local environment of the Sun, cosmic-ray astrophysics, and even paleontology and biological mass extinctions. The scientists are also dedicated to bringing their science to the public through multiple types of public outreach.The research will involve a theoretical study to (1) determine the allowed range of supernova distances and epochs, (2) study mass, nucleosynthesis, and dust formation properties of the supernovae, and (3) develop models for the propagation, evolution, and survival of charged supernova dust in a magnetized medium, in order to understand the observed duration of supernova debris fallout. The results will have implications for supernova explosion models, for supernova remnants, and for dust production in high-redshift galaxies. The outreach activities will include three efforts: (1) bringing astronomy and astrophysics to college-level students in a local state prison, using research to spark discussion and interest. (2) leveraging the April 8, 2024 solar eclipse as an opportunity to bring astronomy and astrophysics to the public and to illustrate how the cosmos intervenes in our lives in ways often imperceptible but sometimes dramatic, and (3) giving frequent public talks on campus and in schools, churches, and community groups.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.