DOI: 10.1002/2015GL066599
论文题名: Evolution of the plasma environment of comet 67P from spacecraft potential measurements by the Rosetta Langmuir probe instrument
作者: Odelstad E. ; Eriksson A.I. ; Edberg N.J.T. ; Johansson F. ; Vigren E. ; André M. ; Tzou C.-Y. ; Carr C. ; Cupido E.
刊名: Geophysical Research Letters
ISSN: 0094-8357
EISSN: 1944-8088
出版年: 2015
卷: 42, 期: 23 起始页码: 10126
结束页码: 10134
语种: 英语
英文关键词: comet
; Langmuir probe
; plasma
; Rosetta
; RPC
; spacecraft potential
Scopus关键词: Carrier concentration
; Electron density measurement
; Electrons
; Langmuir probes
; Orbits
; Particle spectrometers
; Plasma density
; Plasmas
; Probes
; Spacecraft
; Comet
; Heliocentric distances
; Northern Hemispheres
; Plasma environments
; Potential measurements
; Rosetta
; RPC
; Southern Hemisphere
; Electron temperature
; comet
; electron density
; plasma
; spacecraft
英文摘要: 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 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 the Cometary Pressure Sensor of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis. 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 or below a factor of 8-12, consistent with seasonal insolation change. © 2015. American Geophysical Union. All Rights Reserved. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84953635157&doi=10.1002%2f2015GL066599&partnerID=40&md5=a114e3294a9a479276a296090923e8fb
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/7973
Appears in Collections: 科学计划与规划 气候变化与战略
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作者单位: Swedish Institute of Space Physics, Uppsala, Sweden
Recommended Citation:
Odelstad E.,Eriksson A.I.,Edberg N.J.T.,et al. Evolution of the plasma environment of comet 67P from spacecraft potential measurements by the Rosetta Langmuir probe instrument[J]. Geophysical Research Letters,2015-01-01,42(23).