Journal
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volume 462, Issue -, Pages S45-S56Publisher
OXFORD UNIV PRESS
DOI: 10.1093/mnras/stw2112
Keywords
Sun: coronal mass ejections (CMEs); solar wind; comets: individual: 67P/Churyumov-Gerasimenko
Categories
Funding
- Swedish National Space Board [109/12, 135/13, 166/14, 114/13]
- Vetenskapsradet [621-2013-4191, 621-2014-5526]
- German Ministerium fur Wirtschaft und Energie
- Deutsches Zentrum fur Luft- und Raumfahrt [50QP 1401]
- US National Aeronautics and Space Administration [1345493]
- Jet Propulsion Laboratory, California Institute of Technology
- CNES
- ANR [ANR-15-CE31-0009-01]
- Research Council of Norway [240000]
- CNRS
- Observatoire de Paris
- Universite Paul Sabatier, Toulouse
- UK Science and Technology Facilities Council
- Austrian Science Fund (FWF) [P26174] Funding Source: Austrian Science Fund (FWF)
- Austrian Science Fund (FWF) [P 26174] Funding Source: researchfish
- Science and Technology Facilities Council [ST/H002383/1] Funding Source: researchfish
- UK Space Agency [ST/P002250/1, ST/K001698/1] Funding Source: researchfish
- STFC [ST/H002383/1] Funding Source: UKRI
Ask authors/readers for more resources
We present Rosetta observations from comet 67P/Churyumov-Gerasimenko during the impact of a coronal mass ejection (CME). The CME impacted on 2015 Oct 5-6, when Rosetta was about 800 km from the comet nucleus, and 1.4 au from the Sun. Upon impact, the plasma environment is compressed to the level that solar wind ions, not seen a few days earlier when at 1500 km, now reach Rosetta. In response to the compression, the flux of suprathermal electrons increases by a factor of 5-10 and the background magnetic field strength increases by a factor of similar to 2.5. The plasma density increases by a factor of 10 and reaches 600 cm(-3), due to increased particle impact ionization, charge exchange and the adiabatic compression of the plasma environment. We also observe unprecedentedly large magnetic field spikes at 800 km, reaching above 200 nT, which are interpreted as magnetic flux ropes. We suggest that these could possibly be formed by magnetic reconnection processes in the coma as the magnetic field across the CME changes polarity, or as a consequence of strong shears causing Kelvin-Helmholtz instabilities in the plasma flow. Due to the limited orbit of Rosetta, we are not able to observe if a tail disconnection occurs during the CME impact, which could be expected based on previous remote observations of other CME-comet interactions.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available