Blazing Paths to Observing Stellar and Exoplanet Particle Environments

November 6 - 10, 2023
California Institute of Technology - Pasadena, CA 91125

Workshop Overview:

Now that astronomers are routinely probing the composition and evolution of exoplanet atmospheres, the fields of astrophysics, heliophysics, and exoplanetary science must devote greater attention to the particle environments of planets, i.e., space weather. Particles, although far more difficult to observe than photons, could play a significant role in stellar and planetary evolution. Particles erode and chemically modify planetary atmospheres, affecting climate, water inventories, surface radiation, biogenesis, and bioindicators, key driving science of the next flagship observatory. Meanwhile, the stellar particle wind and mass ejections alter a fundamental stellar property – rotation – in turn affecting stellar magnetic activity and associated radiation that also influences planets.

In the Solar System, space weather is monitored by a host of in situ and remote sensing means. This suite of sensors tracks variations in the solar wind and galactic cosmic rays (GCRs) and impulsive events like coronal mass ejections (CMEs) and solar energetic particle (SEP) events. CMEs can be particularly damaging to planetary atmospheres in their path. In contrast with the present-day Sun, for stars and young solar analogs observations of winds, CMEs, SEPs, and GCRs are scarce at best. This absence is striking because many nearby stars are more magnetically active than the Sun, suggesting they produce more intense space weather.

This workshop will chart a course for the new field of planetary particle environment observation and observation-guided modeling. With the confluence of new Solar System observations, renewed modeling efforts, and a significant community push to understand exoplanet atmospheres, it is time to tackle detecting and characterizing particles in the space environments of planets.

The workshop team will review existing approaches for observing particle phenomena in stellar systems and identify study areas essential to evaluate and mature new promising techniques, defining requirements for any new observatory capabilities needed to implement those that hold the greatest promise. The outcome will be a written report to serve as a central resource around which the community can organize efforts to advance the study of planetary particle environments from a sometimes speculative to a largely observational science.

Team Leads

The study program schedule is available in .pdf here

  • Julián Alvarado-Gómez — Leibniz Institute for Astrophysics Potsdam (AIP)
  • Dave Brain — University of Colorado Boulder
  • Bin Chen — New Jersey Institute of Technology
  • Christina Cohen — Caltech
  • Shannon Curry — University of California, Berkeley
  • Ivey Davis — Caltech
  • Karin Dissauer — NorthWest Research Associates
  • Arika Egan — Johns Hopkins University, APL
  • Alison Farrish — NASA Goddard Space Flight Center
  • Nat Gopalswamy — NASA Goddard Space Flight Center
  • James Green — NASA (Retired)
  • Guillaume Gronoff — SSAI/NASA Langley Research Center
  • Shadia Habbal — University of Hawaii
  • Gregg Hallinan — Caltech
  • Renyu Hu — Jet Propulsion Laboratory, California Institute of Technology
  • Meng Jin — Lockheed Martin Solar & Astrophysics Lab
  • Heather Knutson — Caltech
  • Joseph Lazio — Jet Propulsion Laboratory, California Institute of Technology
  • R.O. Parke Loyd — Eureka Scientific, Inc.
  • James Mason — Johns Hopkins University – APL
  • Ruth Murray-Clay — University of California, Santa Cruz
  • Kosuke Namekata — National Astronomical Observatory of Japan (NAOJ)
  • Laura Neves Ribeiro do Amaral — Arizona State University
  • Rachel Osten — Space Telescope Science Institute (STScI)
  • Antígona Segura — Universidad Nacional Autónoma de México (UNAM)
  • Evgenya Shkolnik — Arizona State University
  • Astrid Veronig — University of Graz
  • Aline Vidotto — Leiden University
  • Maurice Wilson — National Center for Atmospheric Research (NCAR)
  • Yu Xu — Peking University