Observation of the hydrogen corona with SPICAM on Mars Express
A series of seven dedicated Lyman-α observations of exospheric atomic hydrogen in the martian corona were performed in March 2005 with the ultraviolet spectrometer SPICAM on board Mars Express. Two types of observations are analyzed, observations at high illumination (for a solar zenith angle SZA eq...
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ftsorbonneuniv:oai:HAL:hal-00283599v1 2024-09-15T18:36:48+00:00 Observation of the hydrogen corona with SPICAM on Mars Express Chaufray, Jean-Yves Bertaux, Jean-Loup Leblanc, François Quémerais, Eric Service d'aéronomie (SA) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) 2008 https://hal.science/hal-00283599 https://doi.org/10.1016/j.icarus.2008.01.009 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.icarus.2008.01.009 hal-00283599 https://hal.science/hal-00283599 doi:10.1016/j.icarus.2008.01.009 ISSN: 0019-1035 EISSN: 1090-2643 Icarus https://hal.science/hal-00283599 Icarus, 2008, 195 (2), pp.598-613. ⟨10.1016/j.icarus.2008.01.009⟩ Ultraviolet observations atmosphere Mars [SDU.OCEAN]Sciences of the Universe [physics]/Ocean [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] info:eu-repo/semantics/article Journal articles 2008 ftsorbonneuniv https://doi.org/10.1016/j.icarus.2008.01.009 2024-07-25T23:47:59Z A series of seven dedicated Lyman-α observations of exospheric atomic hydrogen in the martian corona were performed in March 2005 with the ultraviolet spectrometer SPICAM on board Mars Express. Two types of observations are analyzed, observations at high illumination (for a solar zenith angle SZA equal to 30°) and observations at low illumination (for a solar zenith angle equal to 90° (terminator), and near the south pole). The measured Lyman-α emission is interpreted as purely resonant scattering of solar photons. Because the Lyman-α emission is optically thick, we use a forward model to analyze this data. Below the exobase, the hydrogen density is described by a diffusive model and above the exobase, it follows Chamberlain's approach without satellite particles. For different hydrogen density profiles between 80 and 50,000 km, the volume emission rates are computed by solving the radiative transfer equation. Such an approach has been used to analyze the Mariner 6, 7 exospheric Lyman-α data during the late 1960s. A reasonable fit of the set of observations is obtained assuming an exobase temperature between 200 and 250 K and an exobase density of ∼1–4 × 10 5 cm −3 in good agreement with photochemical models. Article in Journal/Newspaper South pole HAL Sorbonne Université Icarus 195 2 598 613 |
institution |
Open Polar |
collection |
HAL Sorbonne Université |
op_collection_id |
ftsorbonneuniv |
language |
English |
topic |
Ultraviolet observations atmosphere Mars [SDU.OCEAN]Sciences of the Universe [physics]/Ocean [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] |
spellingShingle |
Ultraviolet observations atmosphere Mars [SDU.OCEAN]Sciences of the Universe [physics]/Ocean [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] Chaufray, Jean-Yves Bertaux, Jean-Loup Leblanc, François Quémerais, Eric Observation of the hydrogen corona with SPICAM on Mars Express |
topic_facet |
Ultraviolet observations atmosphere Mars [SDU.OCEAN]Sciences of the Universe [physics]/Ocean [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] |
description |
A series of seven dedicated Lyman-α observations of exospheric atomic hydrogen in the martian corona were performed in March 2005 with the ultraviolet spectrometer SPICAM on board Mars Express. Two types of observations are analyzed, observations at high illumination (for a solar zenith angle SZA equal to 30°) and observations at low illumination (for a solar zenith angle equal to 90° (terminator), and near the south pole). The measured Lyman-α emission is interpreted as purely resonant scattering of solar photons. Because the Lyman-α emission is optically thick, we use a forward model to analyze this data. Below the exobase, the hydrogen density is described by a diffusive model and above the exobase, it follows Chamberlain's approach without satellite particles. For different hydrogen density profiles between 80 and 50,000 km, the volume emission rates are computed by solving the radiative transfer equation. Such an approach has been used to analyze the Mariner 6, 7 exospheric Lyman-α data during the late 1960s. A reasonable fit of the set of observations is obtained assuming an exobase temperature between 200 and 250 K and an exobase density of ∼1–4 × 10 5 cm −3 in good agreement with photochemical models. |
author2 |
Service d'aéronomie (SA) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Chaufray, Jean-Yves Bertaux, Jean-Loup Leblanc, François Quémerais, Eric |
author_facet |
Chaufray, Jean-Yves Bertaux, Jean-Loup Leblanc, François Quémerais, Eric |
author_sort |
Chaufray, Jean-Yves |
title |
Observation of the hydrogen corona with SPICAM on Mars Express |
title_short |
Observation of the hydrogen corona with SPICAM on Mars Express |
title_full |
Observation of the hydrogen corona with SPICAM on Mars Express |
title_fullStr |
Observation of the hydrogen corona with SPICAM on Mars Express |
title_full_unstemmed |
Observation of the hydrogen corona with SPICAM on Mars Express |
title_sort |
observation of the hydrogen corona with spicam on mars express |
publisher |
HAL CCSD |
publishDate |
2008 |
url |
https://hal.science/hal-00283599 https://doi.org/10.1016/j.icarus.2008.01.009 |
genre |
South pole |
genre_facet |
South pole |
op_source |
ISSN: 0019-1035 EISSN: 1090-2643 Icarus https://hal.science/hal-00283599 Icarus, 2008, 195 (2), pp.598-613. ⟨10.1016/j.icarus.2008.01.009⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.icarus.2008.01.009 hal-00283599 https://hal.science/hal-00283599 doi:10.1016/j.icarus.2008.01.009 |
op_doi |
https://doi.org/10.1016/j.icarus.2008.01.009 |
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Icarus |
container_volume |
195 |
container_issue |
2 |
container_start_page |
598 |
op_container_end_page |
613 |
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