Accession Number : AD1034503


Title :   Sesquinary Catenae on the Martian Satellite Phobos from Reaccretion of Escaping Ejecta


Descriptive Note : Journal Article - Open Access


Corporate Author : Air Force Institute of Technology Wright Patterson AFB United States


Personal Author(s) : Nayak,Michael ; Asphaug,Erik


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/1034503.pdf


Report Date : 30 Aug 2016


Pagination or Media Count : 9


Abstract : The Martian satellite Phobos is criss-crossed by linear grooves and crater chains whose origin is unexplained. Anomalous grooves are relatively young, and crosscut tidally predicted stress fields as Phobos spirals towards Mars. Here we report strong correspondence between these anomalous features and reaccretion patterns of sesquinary ejecta from impacts on Phobos. Escaping ejecta persistently imprint Phobos with linear, low-velocity crater chains (catenae)that match the geometry and morphology of prominent features that do not fit the tidal model. We prove that these cannot be older than Phobos current orbit inside Mars Roche limit. Distinctive reimpact patterns allow sesquinary craters to be traced back to their source, for the first time across any planetary body, creating a novel way to probe planetary surface characteristics. For example, we show that catena-producing craters likely formed in the gravity regime, providing constraints on the ejecta velocity field and knowledge of source crater material properties.


Descriptors :   planetary sciences , craters , ARTIFICIAL SATELLITES , ejecta , MARS PLANET


Subject Categories : Astronomy


Distribution Statement : APPROVED FOR PUBLIC RELEASE