Details

Autor(en) / Beteiligte

• Benna, M.
• Mahaffy, P. R.
• Grebowsky, J. M.
• Fox, J. L.
• Yelle, R. V.
• Jakosky, B. M.

Titel

First measurements of composition and dynamics of the Martian ionosphere by MAVEN's Neutral Gas and Ion Mass Spectrometer

Ist Teil von

• Geophysical research letters, 2015-11, Vol.42 (21), p.8958-8965

Ort / Verlag

Washington: Blackwell Publishing Ltd

Erscheinungsjahr

2015

Link zum Volltext

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• We report the results of the observations of the ionosphere of Mars by the Neutral Gas and Ion Mass Spectrometer. These observations were conducted during the first 8 months of the Mars Atmosphere and Volatile EvolutioN mission (MAVEN). These observations revealed the spatial and temporal structures in the density distributions of 22 ions: H2+, H3+, He+, O2+, C+, CH+, N+, NH+, O+, OH+, H2O+, H3O+, N2+/CO+, HCO+/HOC+/N2H+, NO+, HNO+, O2+, HO2+, Ar+, ArH+, CO2+, and OCOH+. Dusk/dawn and day/night asymmetries in the density distributions were observed for nearly all ion species. Additionally, high‐density fluctuations were detected on the nightside and may reflect the effect of the partial screening of the atmosphere of Mars by the weak intrinsic magnetic field of the planet. The two first MAVEN “deep dip” campaigns were used to investigate the location of the primary ion peak. This peak was detected at 190 km near the terminator but was below the spacecraft altitude of 130 km near the subsolar point. Key Points Several ionospheric species were detected during the first 8 months of the MAVEN mission The major ion density peak was detected near the terminator at 190 km altitude The density profiles of all ions exhibit day/night and dusk/dawn asymmetries