First measurements of Jupiter's zonal winds with visible imaging spectroscopy
- Others:
- Joseph Louis LAGRANGE (LAGRANGE) ; Université Nice Sophia Antipolis (1965 - 2019) (UNS) ; COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur ; COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-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)
- New Mexico Institute of Mining and Technology [New Mexico Tech] (NMT)
- Institut d'astrophysique spatiale (IAS) ; Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- NMSU, Dept Astron, Las Cruces, NM USA
- Tokyo Institute of Technology [Tokyo] (TITECH)
- Department of Earth and Planetary Science [Tokyo] ; Graduate School of Science [Tokyo] ; The University of Tokyo (UTokyo)-The University of Tokyo (UTokyo)
- Department of Mechanical and Aerospace Engineering [Las Cruces] ; New Mexico State University
- ANR-15-IDEX-0001,UCA JEDI,Idex UCA JEDI(2015)
- ANR-15-CE31-0014,JOVIAL,Jupiter : Oscillations en Vitesse radiale par ImAgerie multi Longitudes(2015)
Description
We present the first measurements of Jupiter's wind profile ever obtained with Doppler velocity measurements in the visible. Hitherto, knowledge about atmospheric dynamics has been obtained with cloud-tracking techniques , which consist of tracking visible features from images taken at different dates. However, cloud tracking indicates the motion of large cloud structures, which is an indication of the speed of iso-pressure regions, rather than the speed of the actual atmospheric particles. Doppler imaging is as challenging-motions are usually less than 100 m s 1-as appealing because it measures the speed of cloud particles instead of large cloud structures. Significant difference could appear in the case of atmospheric waves interfering with cloud structures. Here we present the first scientific results of a Doppler imaging spectrometer that is dedicated to giant-planet seismology and atmospheric dynamics by providing instantaneous line-of-sight-velocity maps of the planets of the solar system. The instrument has been developed in the framework of the projects JOVIAL (Jovian Oscillations through Velocity Images At several Longitudes) and JIVE in NM (Jovian Interiors from Velocimetry Experiment in New Mexico). It is a Fourier transform spectrometer with a fixed optical path difference working in the mid-visible domain, which monitors the position of solar Fraunhofer lines that are reflected in the planets' upper atmospheres. After describing the instrument principle and the different steps of data reduction, we report measurement of the average zonal wind speed of Jupiter, as a function of latitude, from datasets obtained in 2015 and 2016 with two different telescopes, when the planet was close to its opposition. Our results are consistent between the two years. We compare the results with wind profiles obtained by cloud tracking on HST (Hubble Space Telescope) images taken at the same epoch, and identify a significant discrepancy in the North Equatorial Belt and northern part of the Equatorial Zone.
Abstract
International audience
Additional details
- URL
- https://hal.archives-ouvertes.fr/hal-02105121
- URN
- urn:oai:HAL:hal-02105121v1
- Origin repository
- UNICA