Search

Your search keyword '"Chris Piker"' showing total 5 results
Start Over Author "Chris Piker" Topic astronomy
5 results on '"Chris Piker"'

1. Plasma waves in the inner Jovian magnetosphere at low to mid-latitudes

Author

John E. C. Connerney, Jeremy Faden, Darrelle Wilkinson, Ali Sulaiman, Barry Mauk, George Hospodarsky, S. S. Elliott, William S. Kurth, Chris Piker, Frederic Allegrini, John Menietti, and Scott Bolton

Subjects
Physics, Middle latitudes, Physics::Space Physics, Astronomy, Magnetosphere, Astrophysics::Earth and Planetary Astrophysics, Plasma, Jovian
Abstract

Juno's highly eccentric polar orbit was designed to provide the first measurements at low altitudes over the poles to explore Jupiter’s polar magnetosphere and auroras. Orbit precession moves the initially equatorial perijove to higher northern latitudes at a rate of about one degree per orbit. One result of the precession is that Juno crosses the equator at decreasing radial distances during the inbound portion of the orbit. Recently, Juno has crossed the magnetic equator at distances of 10 Jovian radii (RJ) and less. Voyager and Galileo observations have shown the magnetic equator inside of 10 RJ to be the site of numerous plasma wave phenomena including whistler-mode hiss, chorus, electron cyclotron harmonics and upper hybrid bands. In addition, this is the location of the plasma sheet at the outer edge of the Io and Europa torii. The Juno orbit, with its near-polar inclination carries the spacecraft through this intriguing region to higher latitudes. This paper examines the evolution of whistler-mode chorus and hiss as well as electron cyclotron waves from the magnetic equator to higher latitudes. While there are now statistical studies of electromagnetic waves at intermediate latitudes based on Galileo and Juno observations, this paper is designed to show details of these wave phenomena utilizing the Juno Waves instrument’s burst mode for high resolution. Each of these wave phenomena has the potential to interact with the electrons in the inner magnetosphere and cause pitch-angle scattering and/or acceleration, so they are important in the flow of mass and energy through the Jovian system.

Published
2021

2. MASER: A Science Ready Toolbox for Low Frequency Radio Astronomy

Author

Alan Loh, Baptiste Cecconi, J. Sky, Laurent Denis, Pierre Le Sidaner, Vincent Génot, Xavier Bonnin, Renaud Savalle, Joseph N. Mafi, Stéphane Erard, A. Coffre, Stéphane Aicardi, Corentin K. Louis, Chris Piker, Sonny Lion, Quynh Nhu Nguyen, P. Zarka, Jeremy Faden, Nicolas André, Markus Demleitner, Jean-Mathias Grießmeier, Laurent Lamy, Todd King, Albert Y. Shih, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Observatoire de Paris, Université Paris sciences et lettres (PSL), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), CNRS-INSU : through ASOV., European Project: 871149,EPN2024-RI, European Project: 654208,H2020,H2020-INFRAIA-2014-2015,EPN2020-RI(2015), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
010504 meteorology & atmospheric sciences, Computer science, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, interoperability, Low frequency, radio astronomy, 7. Clean energy, 01 natural sciences, law.invention, Jupiter, law, Planet, Saturn, Computer Science (miscellaneous), Maser, lcsh:Science (General), Instrumentation and Methods for Astrophysics (astro-ph.IM), 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Radio astronomy, Tools, Interoperability, 05 social sciences, Astronomy, Space physics, Galaxy, Computer Science Applications, [SDU]Sciences of the Universe [physics], tools, 0509 other social sciences, Ionosphere, Astrophysics - Instrumentation and Methods for Astrophysics, 050904 information & library sciences, Astrophysics - Earth and Planetary Astrophysics, lcsh:Q1-390
Abstract

MASER (Measurements, Analysis, and Simulation of Emission in the Radio range) is a comprehensive infrastructure dedicated to time-dependent low frequency radio astronomy (up to about 50 MHz). The main radio sources observed in this spectral range are the Sun, the magnetized planets (Earth, Jupiter, Saturn), and our Galaxy, which are observed either from ground or space. Ground observatories can capture high resolution data streams with a high sensitivity. Conversely, space-borne instruments can observe below the ionospheric cut-off (at about 10 MHz) and can be placed closer to the studied object. Several tools have been developed in the last decade for sharing space physics data. Data visualization tools developed by various institutes are available to share, display and analyse space physics time series and spectrograms. The MASER team has selected a sub-set of those tools and applied them to low frequency radio astronomy. MASER also includes a Python software library for reading raw data from agency archives., Submitted to Data Science Journal special issue after PV2018 conference

Published
2020

3. The Juno Waves Investigation

Author

D. L. Kirchner, Chris Piker, T. F. Averkamp, W. T. Robison, P. Zarka, George Hospodarsky, B. T. Mokrzycki, M. Sampl, William S. Kurth, University of Iowa [Iowa City], Department of Physics and Astronomy [Iowa City], 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, and 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)

Subjects
[PHYS]Physics [physics], Physics, Solar System, 010504 meteorology & atmospheric sciences, Waves in plasmas, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, Magnetosphere, Astronomy and Astrophysics, 7. Clean energy, 01 natural sciences, Astrobiology, Jupiter, Atmosphere, Planetary science, Exploration of Jupiter, Space and Planetary Science, Physics::Space Physics, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Magnetosphere of Jupiter, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

Jupiter is the source of the strongest planetary radio emissions in the solar system. Variations in these emissions are symptomatic of the dynamics of Jupiter’s magnetosphere and some have been directly associated with Jupiter’s auroras. The strongest radio emissions are associated with Io’s interaction with Jupiter’s magnetic field. In addition, plasma waves are thought to play important roles in the acceleration of energetic particles in the magnetosphere, some of which impact Jupiter’s upper atmosphere generating the auroras. Since the exploration of Jupiter’s polar magnetosphere is a major objective of the Juno mission, it is appropriate that a radio and plasma wave investigation is included in Juno’s payload. This paper describes the Waves instrument and the science it is to pursue as part of the Juno mission.

Published
2017

4. The influence of Titan on Saturn kilometric radiation

Author

Chris Piker, J. D. Menietti, Baptiste Cecconi, and Shengyi Ye

Subjects
Atmospheric Science, Waves in plasmas, Field line, Direction finding, lcsh:QC801-809, Astronomy, Electron precipitation, Geology, Astronomy and Astrophysics, lcsh:QC1-999, Astrobiology, lcsh:Geophysics. Cosmic physics, symbols.namesake, Space and Planetary Science, Midnight, Local time, Magnetosphere of Saturn, Earth and Planetary Sciences (miscellaneous), symbols, lcsh:Q, lcsh:Science, Titan (rocket family), lcsh:Physics
Abstract

Previous studies have shown that the occurrence probability of Saturn Kilometric Radiation (SKR) appears to be influenced by the local time of Titan. Using a more extensive set of data than the original study, we confirm the correlation of higher occurrence probability of SKR when Titan is located near local midnight. In addition, the direction finding capability of the Cassini Radio Plasma Wave instrument (RPWS) is used to determine if this radio emission emanates from particular source regions. We find that most source regions of SKR are located in the mid-morning sector of local time even when Titan is located near midnight. However, some emission does appear to have a source in the Saturnian nightside, consistent with electron precipitation from field lines that have recently mapped to near Titan.

Published
2010

5. A survey of Galileo plasma wave instrument observations of Jovian whistler-mode chorus

Author

D. A. Gurnett, Chris Piker, George Hospodarsky, Richard B. Horne, J. D. Menietti, and J. B. Groene

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, Magnetic dip, Astrophysics, 01 natural sciences, Jovian, Relativistic particle, Jupiter, symbols.namesake, 0103 physical sciences, Earth and Planetary Sciences (miscellaneous), lcsh:Science, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Waves in plasmas, lcsh:QC801-809, Astronomy, Geology, Astronomy and Astrophysics, lcsh:QC1-999, Particle acceleration, lcsh:Geophysics. Cosmic physics, 13. Climate action, Space and Planetary Science, Van Allen radiation belt, Physics::Space Physics, symbols, lcsh:Q, Astrophysics::Earth and Planetary Astrophysics, Galileo (vibration training), lcsh:Physics
Abstract

A survey of plasma wave observations at Jupiter obtained by the plasma wave instrument on board the Galileo spacecraft is presented. The observations indicate that chorus emissions are observed commonly in the Jovian magnetosphere near the magnetic equator in the approximate radial range 6

Catalog

Books, media, physical & digital resources
See catalog results