NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
A Comet Engulfs Mars: MAVEN Observations of Comet Siding Spring's Influence on the Martian MagnetosphereThe nucleus of comet C/2013 A1 (Siding Spring) passed within 141,000 km of Mars on 19 October 2014. Thus, the cometary coma and the plasma it produces washed over Mars for several hours producing significant effects in the Martian magnetosphere and upper atmosphere. We present observations from Mars Atmosphere and Volatile EvolutioN's (MAVEN's) particles and field's instruments that show the Martian magnetosphere was severely distorted during the comet's passage. We note four specific major effects: (1) a variable induced magnetospheric boundary, (2) a strong rotation of the magnetic field as the comet approached, (3) severely distorted and disordered ionospheric magnetic fields during the comet's closest approach, and (4) unusually strong magnetosheath turbulence lasting hours after the comet left. We argue that the comet produced effects comparable to that of a large solar storm (in terms of incident energy) and that our results are therefore important for future studies of atmospheric escape, MAVEN's primary science objective.
Document ID
20160005828
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Espley, Jared R. (NASA Goddard Space Flight Center Greenbelt, MD United States)
Dibraccio, Gina A. (Universities Space Research Association Greenbelt, MD, United States)
Connerney, John E. P. (Adnet Systems, Inc. Greenbelt, MD, United States)
Brain, David (Colorado Univ. Boulder, CO, United States)
Gruesbeck, Jacob (Maryland Univ. College Park, MD, United States)
Soobiah, Yasir (Maryland Univ. College Park, MD, United States)
Halekas, Jasper S. (Colorado Univ. Boulder, CO, United States)
Combi, Michael (NASA Ames Research Center Moffett Field, CA, United States)
Luhmann, Janet (Colorado Univ. Boulder, CO, United States)
Ma, Yingjuan (NASA Ames Research Center Moffett Field, CA, United States)
Date Acquired
May 4, 2016
Publication Date
November 5, 2015
Publication Information
Publication: Geophysical Research Letters
Volume: 42
Issue: 21
ISSN: ?0094-8276
Subject Category
Physics of Elementary Particles and Fields
Solar Physics
Report/Patent Number
GSFC-E-DAA-TN31409
Funding Number(s)
CONTRACT_GRANT: NNH15CO48B
CONTRACT_GRANT: NNG12PL17C
CONTRACT_GRANT: NNG06EO90A
Distribution Limits
Public
Copyright
Other
Keywords
Nucleus
Martian
Siding Spring