Cassini microwave radiometry observations of Enceladus' South Pole: Detection of a warm subsurface?

At the beginning of the Cassini mission, the ISS (Imaging Science Subsystem) and CIRS (Composite Infra-Red Spectrometer) instruments discovered a geologically active region at the south pole of Saturn's moon Enceladus (e.g. Porco et al., 2005). Plumes venting material emanate from this region....

Full description

Bibliographic Details
Main Authors: Le Gall, Alice, Leyrat, Cedric, Janssen, Michael A., Stolzenbach, Aurélien, Wye, Lauren C., West, Richard D., Lorenz, Ralph D., Mitchell, Karl L.
Other Authors: PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), 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)-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), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Stanford University
Format: Conference Object
Language:English
Published: HAL CCSD 2012
Subjects:
Online Access:https://hal.science/hal-00768858
id ftuniversailles:oai:HAL:hal-00768858v1
record_format openpolar
spelling ftuniversailles:oai:HAL:hal-00768858v1 2024-05-19T07:48:37+00:00 Cassini microwave radiometry observations of Enceladus' South Pole: Detection of a warm subsurface? Le Gall, Alice Leyrat, Cedric Janssen, Michael A. Stolzenbach, Aurélien Wye, Lauren C. West, Richard D. Lorenz, Ralph D. Mitchell, Karl L. PLANETO - LATMOS Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS) 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)-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) Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA) Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS) Jet Propulsion Laboratory (JPL) NASA-California Institute of Technology (CALTECH) Stanford University San Francisco, United States 2012-12-03 https://hal.science/hal-00768858 en eng HAL CCSD hal-00768858 https://hal.science/hal-00768858 AGU Fall Meeting https://hal.science/hal-00768858 AGU Fall Meeting, Dec 2012, San Francisco, United States Saturnian satellites Remote sensing Surface materials and properties [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP] [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP] info:eu-repo/semantics/conferenceObject Conference papers 2012 ftuniversailles 2024-04-25T00:14:31Z At the beginning of the Cassini mission, the ISS (Imaging Science Subsystem) and CIRS (Composite Infra-Red Spectrometer) instruments discovered a geologically active region at the south pole of Saturn's moon Enceladus (e.g. Porco et al., 2005). Plumes venting material emanate from this region. Six years later, on November 6, 2011, the first-ever Synthetic Aperture Radar (SAR) image of Enceladus was acquired during the E16 flyby of the moon at the wavelength of 2-cm (Mitchell et al., AGU 2011). The SAR swath is located within the seemingly young South Pole Terrains, not far from the active sulci also known as the "tiger stripes" identified as the sources of the plumes. Concurrently to the SAR image, radiometry data were collected in the passive mode of the instrument with a ground footprint of 25-40 km across the track and ~5 km along. The Cassini radiometer records the thermal emission from the surface in the microwave domain, at 2-cm. More specifically, it measures the brightness temperature of the surface that varies both with the emissivity and the vertical temperature profile below the surface down to a depth, which depends on the electrical properties of the subsurface. Typically, radio instruments sense 10 to 100 wavelengths into an icy crust and can thus provide unique insight into the compositional, thermal and physical (porosity, roughness) state of planetary regoliths at depths much greater than the ones sampled by thermal IR spectrometers. In particular, microwave radiometer can be used to detect possible endogenic activity beneath the surface. The measured calibrated brightness temperatures during E16 cover a range from 33 to 60 K. In order to analyze these dataset, we have modeled the expected thermal emission from Enceladus' surface. In absence of endogenic emission, the temperature structure of any airless satellite results from a balance between solar insolation, heat transport within the subsurface and reradiation outward. The developed thermal model accounts not only for the diurnal but also ... Conference Object South pole Université de Versailles Saint-Quentin-en-Yvelines: HAL-UVSQ
institution Open Polar
collection Université de Versailles Saint-Quentin-en-Yvelines: HAL-UVSQ
op_collection_id ftuniversailles
language English
topic Saturnian satellites
Remote sensing
Surface materials and properties
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
[PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
spellingShingle Saturnian satellites
Remote sensing
Surface materials and properties
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
[PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Le Gall, Alice
Leyrat, Cedric
Janssen, Michael A.
Stolzenbach, Aurélien
Wye, Lauren C.
West, Richard D.
Lorenz, Ralph D.
Mitchell, Karl L.
Cassini microwave radiometry observations of Enceladus' South Pole: Detection of a warm subsurface?
topic_facet Saturnian satellites
Remote sensing
Surface materials and properties
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
[PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
description At the beginning of the Cassini mission, the ISS (Imaging Science Subsystem) and CIRS (Composite Infra-Red Spectrometer) instruments discovered a geologically active region at the south pole of Saturn's moon Enceladus (e.g. Porco et al., 2005). Plumes venting material emanate from this region. Six years later, on November 6, 2011, the first-ever Synthetic Aperture Radar (SAR) image of Enceladus was acquired during the E16 flyby of the moon at the wavelength of 2-cm (Mitchell et al., AGU 2011). The SAR swath is located within the seemingly young South Pole Terrains, not far from the active sulci also known as the "tiger stripes" identified as the sources of the plumes. Concurrently to the SAR image, radiometry data were collected in the passive mode of the instrument with a ground footprint of 25-40 km across the track and ~5 km along. The Cassini radiometer records the thermal emission from the surface in the microwave domain, at 2-cm. More specifically, it measures the brightness temperature of the surface that varies both with the emissivity and the vertical temperature profile below the surface down to a depth, which depends on the electrical properties of the subsurface. Typically, radio instruments sense 10 to 100 wavelengths into an icy crust and can thus provide unique insight into the compositional, thermal and physical (porosity, roughness) state of planetary regoliths at depths much greater than the ones sampled by thermal IR spectrometers. In particular, microwave radiometer can be used to detect possible endogenic activity beneath the surface. The measured calibrated brightness temperatures during E16 cover a range from 33 to 60 K. In order to analyze these dataset, we have modeled the expected thermal emission from Enceladus' surface. In absence of endogenic emission, the temperature structure of any airless satellite results from a balance between solar insolation, heat transport within the subsurface and reradiation outward. The developed thermal model accounts not only for the diurnal but also ...
author2 PLANETO - LATMOS
Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS)
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)-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)
Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA)
Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris
Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
Jet Propulsion Laboratory (JPL)
NASA-California Institute of Technology (CALTECH)
Stanford University
format Conference Object
author Le Gall, Alice
Leyrat, Cedric
Janssen, Michael A.
Stolzenbach, Aurélien
Wye, Lauren C.
West, Richard D.
Lorenz, Ralph D.
Mitchell, Karl L.
author_facet Le Gall, Alice
Leyrat, Cedric
Janssen, Michael A.
Stolzenbach, Aurélien
Wye, Lauren C.
West, Richard D.
Lorenz, Ralph D.
Mitchell, Karl L.
author_sort Le Gall, Alice
title Cassini microwave radiometry observations of Enceladus' South Pole: Detection of a warm subsurface?
title_short Cassini microwave radiometry observations of Enceladus' South Pole: Detection of a warm subsurface?
title_full Cassini microwave radiometry observations of Enceladus' South Pole: Detection of a warm subsurface?
title_fullStr Cassini microwave radiometry observations of Enceladus' South Pole: Detection of a warm subsurface?
title_full_unstemmed Cassini microwave radiometry observations of Enceladus' South Pole: Detection of a warm subsurface?
title_sort cassini microwave radiometry observations of enceladus' south pole: detection of a warm subsurface?
publisher HAL CCSD
publishDate 2012
url https://hal.science/hal-00768858
op_coverage San Francisco, United States
genre South pole
genre_facet South pole
op_source AGU Fall Meeting
https://hal.science/hal-00768858
AGU Fall Meeting, Dec 2012, San Francisco, United States
op_relation hal-00768858
https://hal.science/hal-00768858
_version_ 1799466921203073024