TY - JOUR
T1 - A Complete Data Set of Equatorial Projections of Saturn's Energetic Neutral Atom Emissions Observed by Cassini-INCA
AU - Bader, A.
AU - Kinrade, J.
AU - Badman, S. V.
AU - Paranicas, C.
AU - Constable, D. A.
AU - Mitchell, D. G.
N1 - Funding Information:
Cassini operations are supported by NASA (managed by the Jet Propulsion Laboratory) and European Space Agency (ESA). A. Bader was funded by a Lancaster University FST studentship. J. Kinrade, S. V. Badman, and D. A. Constable were supported by STFC Grant ST/R000816/1. S. V. Badman was also supported by an STFC Ernest Rutherford Fellowship ST/M005534/1. C. Paranicas would like to acknowledge Grants 80NSSC19K0886 and NNX16AI46G between NASA and the Johns Hopkins University. Computations for this study were performed using the High End Computing facility at Lancaster University.
Funding Information:
Cassini operations are supported by NASA (managed by the Jet Propulsion Laboratory) and European Space Agency (ESA). A. Bader was funded by a Lancaster University FST studentship. J. Kinrade, S. V. Badman, and D. A. Constable were supported by STFC Grant ST/R000816/1. S. V. Badman was also supported by an STFC Ernest Rutherford Fellowship ST/M005534/1. C. Paranicas would like to acknowledge Grants 80NSSC19K0886 and NNX16AI46G between NASA and the Johns Hopkins University. Computations for this study were performed using the High End Computing facility at Lancaster University.
Publisher Copyright:
© 2021. The Authors.
PY - 2021/6
Y1 - 2021/6
N2 - Observations of energetic neutral atoms (ENAs) are a useful tool for analyzing ion and neutral abundances in planetary magnetospheres. They are created when hot plasma, originating for example from magnetic reconnection sites, charge-exchanges with the ambient neutral population surrounding the planet. The motion of ENAs is not governed by the magnetic field, allowing remote imaging. During the Cassini mission, the Ion and Neutral CAmera (INCA) of the Magnetosphere Imaging Instrument (MIMI) collected vast amounts of hydrogen and oxygen ENA observations of Saturn's magnetosphere from a variety of different viewing geometries. To enable investigations of the morphology and dynamics of Saturn's ring current, it is useful to re-bin and re-project the camera-like views from the spacecraft-based perspective into a common reference frame. We developed an algorithm projecting INCA's ENA observations into a regular grid in Saturn's equatorial plane. With most neutrals and ions being confined into an equatorial rotating disc, this projection is quite accurate in both spatial location and preservation of ENA intensity, provided the spacecraft is located at large enough elevations. Such projections were performed for all INCA ENA data from the Cassini Saturn tour; the data are available for download together with a Python routine flagging contaminated data and returning detailed spacecraft geometry information. The resulting data set is a good foundation for investigating for example the statistical properties of Saturn's ring current and its complicated dynamics in relation to other remote and in situ observations of, for example, auroral emissions and magnetotail reconnection events.
AB - Observations of energetic neutral atoms (ENAs) are a useful tool for analyzing ion and neutral abundances in planetary magnetospheres. They are created when hot plasma, originating for example from magnetic reconnection sites, charge-exchanges with the ambient neutral population surrounding the planet. The motion of ENAs is not governed by the magnetic field, allowing remote imaging. During the Cassini mission, the Ion and Neutral CAmera (INCA) of the Magnetosphere Imaging Instrument (MIMI) collected vast amounts of hydrogen and oxygen ENA observations of Saturn's magnetosphere from a variety of different viewing geometries. To enable investigations of the morphology and dynamics of Saturn's ring current, it is useful to re-bin and re-project the camera-like views from the spacecraft-based perspective into a common reference frame. We developed an algorithm projecting INCA's ENA observations into a regular grid in Saturn's equatorial plane. With most neutrals and ions being confined into an equatorial rotating disc, this projection is quite accurate in both spatial location and preservation of ENA intensity, provided the spacecraft is located at large enough elevations. Such projections were performed for all INCA ENA data from the Cassini Saturn tour; the data are available for download together with a Python routine flagging contaminated data and returning detailed spacecraft geometry information. The resulting data set is a good foundation for investigating for example the statistical properties of Saturn's ring current and its complicated dynamics in relation to other remote and in situ observations of, for example, auroral emissions and magnetotail reconnection events.
UR - https://www.scopus.com/pages/publications/85107686066
UR - https://www.scopus.com/pages/publications/85107686066#tab=citedBy
U2 - 10.1029/2020JA028908
DO - 10.1029/2020JA028908
M3 - Article
AN - SCOPUS:85107686066
SN - 2169-9380
VL - 126
JO - Journal of Geophysical Research: Space Physics
JF - Journal of Geophysical Research: Space Physics
IS - 6
M1 - e2020JA028908
ER -