Airfall on Comet 67P/Churyumov–Gerasimenko

Björn J.R. Davidsson, Samuel Birch, Geoffrey A. Blake, Dennis Bodewits, Jason P. Dworkin, Daniel P. Glavin, Yoshihiro Furukawa, Jonathan I. Lunine, Julie L. Mitchell, Ann N. Nguyen, Steve Squyres, Aki Takigawa, Jean Baptiste Vincent, Kris Zacny

研究成果: Article査読

15 被引用数 (Scopus)


We here study the transfer process of material from one hemisphere to the other (deposition of airfall material) on an active comet nucleus, specifically 67P/Churyumov–Gerasimenko. Our goals are to: 1) quantify the thickness of the airfall debris layers and how it depends on the location of the target area, 2) determine the amount of H2O and CO2 ice that are lost from icy dust assemblages of different sizes during transfer through the coma, and 3) estimate the relative amount of vapor loss in airfall material after deposition in order to understand what locations are expected to be more active than others on the following perihelion approach. We use various numerical simulations, that include orbit dynamics, thermophysics of the nucleus and of individual coma aggregates, coma gas kinetics and hydrodynamics, as well as dust dynamics due to gas drag, to address these questions. We find that the thickness of accumulated airfall material varies substantially with location, and typically is of the order 0.1–1 m. The airfall material preserves substantial amounts of water ice even in relatively small (cm–sized) coma aggregates after a rather long (12 h) residence in the coma. However, CO2 is lost within a couple of hours even in relatively large (dm–sized) aggregates, and is not expected to be an important component in airfall deposits. We introduce reachability and survivability indices to measure the relative capacity of different regions to simultaneously collect airfall and to preserve its water ice until the next perihelion passage, thereby grading their potential of contributing to comet activity during the next perihelion passage.

出版ステータスPublished - 2021 1月 15

ASJC Scopus subject areas

  • 天文学と天体物理学
  • 宇宙惑星科学


「Airfall on Comet 67P/Churyumov–Gerasimenko」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。