EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Juno’s Exploration of Jupiter’s Magnetic Field and Magnetosphere

Jack Connerney1,2, Ron Oliverson2, Stavros Kotsiaros2,3,4, Dan Gershman2, Yasmina Martos2, John Joergensen4, Peter Joergensen4, Jose Merayo4, Matija Herceg4, Mathias Benn4, Troelz Denver4, Jeremy Bloxham5, Kimberly Moore5, Scott Bolton6, and Steven Levin7
Jack Connerney et al.
  • 1Space Research Corporation, Annapolis, United States of America (
  • 2NASA Goddard Space Flight Center, Greenbelt, MD, United States.
  • 3University of Maryland, College Park, MD, United States.
  • 4Technical University of Denmark (DTU), Lyngby, Denmark.
  • 5Harvard University, Cambridge, MA, United States.
  • 6Southwest Research Institute, San Antonio, TX, United States.
  • 7Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States.

The Juno spacecraft was inserted into polar orbit about Jupiter on July 4th, 2016, performing close passes (to ~1.05 Rj radial distance at periJove) every 53 days. By the end of its prime mission, Juno will have circled the planet 34 times, uniformly sampling longitudes separated by less than 11 at the equator. The Juno magnetic field investigation is equipped with two magnetometer sensor suites, located at 10 and 12 m from the spacecraft body at the end of one of Juno’s three solar arrays. Each contains a vector fluxgate magnetometer (FGM) sensor and a pair of co-located non-magnetic star tracker camera heads that provide accurate attitude determination for the FGM sensors. A moredetailed view of Jupiter’s planetary dynamo is emerging as Juno acquires more periJove passes, providing spatial resolution beyond that already evident in the preliminary model (JRM09, a degree 10 spherical harmonic) derived from Juno’s first 9 periJoves. A complex and very non-dipolar magnetic field dominates the northern hemisphere, while a mostly dipolar magnetic field is observed south of the equator, where the enigmatic “Great Blue Spot” resides within an equatorial band of opposite polarity. The Jovian magnetodisc, formed by a washer-shaped disc of azimuthal (“ring”) currents, stretches magnetic field lines outward along the magnetic equator. With 26 equally spaced longitudes now available we can begin to address magnetodisc variability, finding a more or less stable system of azimuthal ring currents (few % variability) and a more variable (~50%) system of radial currents that supply torque to outflowing plasma. A new magnetodisc model greatly improves knowledge of the field geometry, independently verified via observations of the particle absorption signatures of Galilean satellites. A more systematic mapping of Birkeland currents above the polar aurorae also emerges from multiple passes. These and other developments will be presented with Juno now about ¾ of the way towards completion of its primary mission.

How to cite: Connerney, J., Oliverson, R., Kotsiaros, S., Gershman, D., Martos, Y., Joergensen, J., Joergensen, P., Merayo, J., Herceg, M., Benn, M., Denver, T., Bloxham, J., Moore, K., Bolton, S., and Levin, S.: Juno’s Exploration of Jupiter’s Magnetic Field and Magnetosphere, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10992,, 2020

This abstract will not be presented.