News

Solar Eclipse
April 16, 2024

Thousands gathered in Princeton’s Palmer Square on Monday, 4/8/24, for a community viewing of the partial solar eclipse.

Volunteers from the Space Physics Group and the Department of Astrophysical Sciences joined the Council on Science and Technology and the Amateur Astronomers Association of Princeton to answer questions and…

Young Women's Conference in STEM
March 25, 2024

On March 15, 2024, at Princeton University, Lengying Khoo, Tejaswita Sharma, and Kimberly Rogan from the Space Physics Group shared information about the IMAP mission with over 800 middle school and high school students at the Young Women’s Conference in STEM.  The conference, hosted by the U.S. Department of Energy’s Princeton Plasma…

Publication: Correlation of Coronal Mass Ejection Shock Temperature with Solar Energetic Particle Intensity
March 21, 2024

Solar energetic particle (SEP) events have been observed by the Parker Solar Probe (PSP) spacecraft since its launch in 2018. These events include sources from solar flares and coronal mass ejections (CMEs). The ISOIS instrument suite on board PSP is measuring ions over energies from ~20 keV nucleon-1 to 200…

Publication: Europa modifies Jupiter’s Plasma Sheet
March 19, 2024

Jupiter's plasma sheet has been understood to be primarily composed of Io‐genic sulfur and oxygen, along with protons at lower mass density. These ions move radially away from Jupiter, filling its magnetosphere. The material in the plasma sheet interacts with Europa, which is also a source of magnetospheric pickup ions, primarily hydrogen and…

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;…