Space Physics at Princeton

Welcome to Space Physics at Princeton

The Space Physics group in the Department of Astrophysical Sciences:

  • Educates Princeton University undergraduate and graduate students through hands-on work in an active space instrument laboratory and with scientific data from space
  • Conceives, designs develops, calibrates, and flies cutting-edge space instrumentation on NASA missions
  • Analyzes space data from the Sun and Solar Corona through to the Solar Wind and terrestrial and planetary magnetospheres, including the global heliosphere and its interaction with the local interstellar medium
  • Discovers scientific secrets of our space environs through integrated observations, data analysis, and theoretical understanding

We are the lead institution for numerous NASA Heliophysics missions and instruments that Prof. David J. McComas serves as the principal investigator for:

Interstellar Mapping and Acceleration Probe (IMAP) mission – under development and launching in 2025 to explore the details of particle acceleration and the Sun’s interaction with the local interstellar medium;

Parker Solar Probe (PSP), Integrated Science investigation of the Sun (ISʘIS) instrument suite – launched 8/12/2018 to measure energetic particles as close in as nine solar radii from the Sun’s surface;

Interstellar Boundary Explorer (IBEX) mission – launched in 2008 and still exploring the boundaries of our heliosphere and its interaction with the local interstellar medium;

New Horizons, Solar Wind Around Pluto (SWAP) instrument – launched in 2006, measured the plasma environments of Pluto and the Jovian magnetosphere and continues to make unprecedented observations of interstellar pickup ions;

Advanced Composition Explorer (ACE), Solar Wind Electron Proton Alpha Monitor (SWEPAM) instrument – launched in 1997 and still providing solar wind data from the Sun-Earth Lagrangian point (L1);

Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) mission – returned the first stereo imaging of the Earth’s dynamic magnetosphere (operational from 2008-2017);

Ulysses, Solar Wind Observations Over the Poles of the Sun (SWOOPS) instrument – discovered the three-dimensional structure of the solar wind from the first and only mission to fly over the poles of the Sun (operational from 1990 - 2009).

 


 

Sun & Princeton Shield

Space Physics Group

The Space Physics Group

The Space Physics Group

Research News

Publication: Multispacecraft Observations of a Widespread Solar Energetic Particle Event on 2022 February 15–16
March 6, 2024

On 2022 February 15–16, multiple spacecraft measured one of the most intense solar energetic particle (SEP) events observed so far in Solar Cycle 25. This study provides an overview of interesting observations made by multiple spacecraft during this event. Parker Solar Probe (PSP) and BepiColombo were close to each other at…

Publication: Resonant Plasma Acceleration at Jupiter Driven by Satellite‐ Magnetosphere Interactions
March 5, 2024

The Juno spacecraft had previously observed intense high frequency wave emission, broadband electron and energetic proton energy distributions within magnetic flux tubes connected to Io, Europa, Ganymede, and their wakes. In this work, we report consistent enhancements in <46 keV energy proton fluxes during these satellite flux tube transit…

Publication: Oxygen production from dissociation of Europa’s water-ice surface
March 4, 2024

Jupiter’s moon Europa has a predominantly water-ice surface that is modified by exposure to its space environment. Charged particles break molecular bonds in surface ice, thus dissociating the water to ultimately produce H2 and O2, which provides a potential oxygenation mechanism for Europa’s subsurface ocean. These species are understood…

Publication: Suprathermal Hydrogen Pickup Ion Tails in the Outer Heliosphere
Dec. 20, 2023

Shrestha et al. performed a detailed analysis of five distant interplanetary shocks observed by the Solar Wind Around Pluto instrument on board New Horizons, which exhibit the signature of a suprathermal H+ pickup ion (PUI) tail in the downstream distribution. These shocks were observed with a PUI data cadence of approximately 24 hr,…

Senior Wolf Cukier featured in Discovery: Research at Princeton magazine
Dec. 19, 2023

Senior Wolf Cukier '24 was featured in the Discovery: Research at Princeton magazine for his efforts on a broad range of research interests. See article here.

Publication: Entropy defect - Algebra and thermodynamics
Nov. 22, 2023

We investigate the way the entropy of a system can be partitioned into the entropies of its constituents in consistency with thermodynamics. This partitioning is described through the concept of an entropy defect, which measures the missing entropy between the sum of entropies of a system's constituents and the entropy of the combined system;…

Publication: Connection between Heating and Polytropes
Oct. 12, 2023

The paper derives the one-to-one connecting relationships between plasma heating and its polytropic index, and addresses the consequences through the transport equation of temperature. Thermodynamic polytropic processes are classified in accordance to their polytropic index, the exponent of the power-law relationship of thermal pressure…

Publication: Estimates of Proton and Electron Heating Rates Extended to the Near-Sun Environment
Sept. 27, 2023

The differential heating of charged species due to dissipation of turbulent fluctuations plays a key role in solar wind evolution. Measurements from previous heliophysics missions have provided estimates of proton and electron heating rates beyond 0.27 au. Using Parker Solar Probe (PSP) data accumulated during the first 10 encounters, we extend…

Publication: Extensive Entropy - the case of Zero Entropy Defect
Sept. 26, 2023

This paper shows that the Rényi and Boltzmann-Gibbs (BG) extensive entropies share the same functional relationship with the nonextensive entropy associated with kappa distributions, which coincides with the well-known Havrda/Charvát/Daróczy/Tsallis (HCDT) entropy. We find that while the relationship between kappa/HCDT and Rényi entropies is…

Publication: Transport equation of kappa distributions in the heliosphere
Aug. 23, 2023

In this paper we develop the transport equation of kappa, the fundamental thermodynamic parameter that labels kappa distributions of particle velocities. Using the recently developed concept of entropy defect, we are able to formulate the transport equation of kappa as a function of a general positive or negative rate of entropy change. Then,…