Planetary Bodies

Using data from NASA’s Parker Solar Probe, we have assembled a comprehensive understanding of our zodiacal cloud's inner structure and behavior, comprised of dust that swirls throughout the solar system. PSP observed three dust populations in the cloud. Most of the grains are being slowly pulled in toward the Sun (alpha-meteoroids); the second population is generated as grains in the swirling cloud collide, creating fragments so small that they are pushed out of the solar system in all directions by pressure from sunlight (beta-meteoroids); and a third group, probably created when a “tube” of cometary debris collides with grains from the first two populations, that is scattered out in a distinctive wedge shape. From these observations, we're able to constrain the collisional evolution of the zodiacal cloud.

Jovian magnetospheric overview
Overview of Jupiter’s magnetosphere in the vicinity of the Galilean satellites. Water-group pickup ions (blue) originate from Europa’s neutral toroidal cloud (brighter blue near Europa). Io and Europa contribute plasma pickup ions of different compositions to Jupiter’s magnetosphere. Alfvén wings connected to the moons due to their interaction with corotating plasma are shown in grey. Credit: Szalay, J. R., et al. (2022). Water-group pickup ions from Europa-genic Neutrals Orbiting Jupiter. Geophysical Research Letters, 49, https://doi.org/10.1029/2022GL098111 

Planetary bodies throughout the solar system are exposed to plasma and dust particle fluxes. Jupiter's plasma environment is of particular interest as it is internally driven by material released from its diverse moons. Observations with the JADE instrument aboard the Juno spacecraft have allowed us to probe the inner workings and composition of Jupiter's plasma environment in unprecedented detail. For example, JADE observations have revealed water-group pickup ions are injected into its magnetosphere from the destruction of water-ice on Europa's surface.

 

Solar Wind Interaction with Pluto
SWAP observations of Pluto's interaction with the solar wind. Credit: McComas, D. J., et al. (2016), J. Geophys. Res., 121, 4232–4246.

 

All objects in the heliosphere also provide an obstacle to the solar wind and will carve out a local interaction region populated with a complex and diverse plasma environment. For example, plasma measurements taken with the SWAP instrument during New Horizons' flyby of Pluto revealed a hybrid interaction, where a bow shock ahead of Pluto is generated by mass-loading of the solar wind like at a comet, but the obstacle excluding the solar wind plasma is supported by atmospheric pressure like the interaction at Venus or Mars. 

For airless bodies that lack dense atmospheres, their surfaces are entirely exposed to local plasma and dust populations, which modify and space weather their surfaces over time. These bodies are both sources and sinks of plasma and dust populations throughout the heliosphere.

Relevant Observations:

  • Solar wind ions, pickup ions, and planetary ions at Jupiter and Pluto (SWAP)
  • Energetic neutral atoms from Earth’s magnetosphere (TWINS, IBEX) and the Moon (IBEX)
  • Plasma at Jupiter’s magnetosphere (Juno/JADE)
  • Dust impact ejecta clouds from the Moon (LADEE)

Examples of Research Topics:

  • Heavy ions at the solar wind interaction with Pluto
  • Auroral processes at Jupiter
  • Satellite-magnetosphere interactions at Jupiter (Io, Europa, Ganymede, Callisto)
  • Impact processes at airless bodies