Citation

BibTex format

@article{Odelstad:2015:10.1002/2015GL066599,
author = {Odelstad, E and Eriksson, AI and Edberg, NJT and Johansson, F and Vigren, E and Andre, M and Tzou, CY and Carr, CM and Cupido, E},
doi = {10.1002/2015GL066599},
journal = {Geophysical Research Letters},
pages = {10126--10134},
title = {Evolution of the plasma environment of comet 67P from spacecraft potential measurements by the Rosetta Langmuir probe instrument},
url = {http://dx.doi.org/10.1002/2015GL066599},
volume = {42},
year = {2015}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - We study the evolution of the plasma environment of comet 67P using measurements of the spacecraft potential from early September 2014 (heliocentric distance 3.5 AU) to late March 2015 (2.1 AU) obtained by the Langmuir probe (RPC-LAP) instrument. The low collision rate keeps the electron temperature high (~ 5 eV), resulting in a negative spacecraft potential whose magnitude depends on the electron density. This potential is more negative in the northern (summer) hemisphere, particularly over sunlit parts of the neck region on the nucleus, consistent with neutral gas measurements by ROSINA-COPS. Assuming constant electron temperature, the spacecraft potential traces the electron density. This increases as the comet approaches the Sun, most clearly in the southern hemisphere by a factor possibly as high as 20 - 44 between September 2014 and January 2015. The northern hemisphere plasma density increase stays around a factor of around or below 8 - 12, consistent with seasonal insolation change.
AU - Odelstad,E
AU - Eriksson,AI
AU - Edberg,NJT
AU - Johansson,F
AU - Vigren,E
AU - Andre,M
AU - Tzou,CY
AU - Carr,CM
AU - Cupido,E
DO - 10.1002/2015GL066599
EP - 10134
PY - 2015///
SN - 1944-8007
SP - 10126
TI - Evolution of the plasma environment of comet 67P from spacecraft potential measurements by the Rosetta Langmuir probe instrument
T2 - Geophysical Research Letters
UR - http://dx.doi.org/10.1002/2015GL066599
UR - http://hdl.handle.net/10044/1/28026
VL - 42
ER -