The small bodies of our and other planetary systems

我们和其他行星系统的小天体

• 批准号: RGPIN-2018-05659
• 负责人: Wiegert, Paul
• 金额: $ 2.99万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=713771
• 关键词: small; bodies; our; other; planetary

The proposed research program is directed at understanding the processes that drive a planetary system from its initial to its present state. This research is to be conducted through the lens of a planetary system's smaller bodies -- dwarf planets, asteroids, comets and meteoroids sub-planetary bodies or SPBs for short. SPBs are abundant, widespread and diverse in size and composition in our own solar system. Most stars in our galaxy also have planetary systems and many are known to contain SPBs as well. As a result, SPBs are rich sources of information at scales from planetary systems up to the Galaxy itself. This research problem will be addressed through three major themes: I) establishing the current reservoirs of sub-planetary bodies in our solar system II) using meteors as low-cost 'sample-return missions' to learn about to their parents in space, and III) using our understanding of the Solar System to explore exoplanetary systems. Sub-planetary bodies are important scientifically. 1) They are the ingredients from which Earth and other planets (both in our system and exoplanetary systems) formed, and so they are 'fossils' from the era of planet birth. 2) SPBs current locations within a planetary system are tracers of large-scale changes within it. For example, did the planets perhaps orbit their star closer to or farther away than they do now? 3) SPBs formed at the same time as their star, providing important insight into the process of star birth. In a broader context, SPBs are important to the study of life on Earth and its environment because 1) they delivered both water and carbon-based organic molecules to our planet, 2) SPBs have shaped life on Earth through large asteroid impacts and extinction events. SPBs are also relevant to society at large. 1) Meteor showers are easily accessible and engage the general public in science. 2) The brightest meteor events ('fireballs'), such as the one over the Russian city of Chelyabinsk in February 2013, constitute an incompletely understood public danger. The Chelyabinsk event was undetected prior to its arrival and released 30 times the energy of the Hiroshima bomb over a major city. The resulting explosion caused $33 million USD damage to buildings, and sent 1500 people for medical treatment. 3) The largest asteroids pose a small but non-negligible threat to our entire planet and have generated responses at the highest political level. For example, in 1994 and again in 2005, US Congress specifically mandated NASA find hazardous near-Earth asteroids and analyze options for deflecting them, This has been reported on by, for example, the NY Times ('NASA faces funding crunch to find killer asteroids', March 12 2007) and Bloomberg ('An Asteroid May Kill Us All. Congress Is Pinching Pennies', May 11 2017). For all these reasons, SPBs are both scientifically interesting and of relevance to Canadians and to the global community.

提出的研究计划旨在了解驱动行星系统从初始状态到现在状态的过程。这项研究将通过行星系统中较小的天体进行——矮行星、小行星、彗星和流星体——次行星体或简称spb。在我们自己的太阳系中，spb数量丰富，分布广泛，大小和组成多种多样。我们银河系中的大多数恒星也有行星系统，其中许多已知也含有spb。因此，从行星系统到银河系本身，spb都是丰富的信息来源。