NRL imager begins solar wind observations aboard NASA PUNCH mission

NRL imager begins solar wind observations aboard NASA PUNCH mission
by Clarence Oxford
Los Angeles CA (SPX) Mar 24, 2025

The U.S. Naval Research Laboratory's (NRL) Narrow Field Imager (NFI) has officially commenced operations in orbit after being launched aboard a SpaceX Falcon 9 rocket as part of NASA's Polarimeter to Unify the Corona and Heliosphere (PUNCH) mission on March 11. The NFI payload successfully deployed from the launch vehicle on March 12 and is now gathering data from low Earth orbit.

PUNCH consists of a quartet of satellites working in unison to study the inner heliosphere. These spacecraft aim to deliver comprehensive, three-dimensional imagery of the region where the solar corona transforms into the solar wind. With a planned two-year science phase following a three-month commissioning period, PUNCH will deliver vital insights into solar wind formation.

NRL's contribution, the NFI, is a compact coronagraph with an external occulter that blocks direct sunlight, allowing it to observe the faint corona and background starfield around the Sun. Its optical assembly includes a compound lens system and a polarizing filter wheel, with imaging handled by a CCD camera featuring a 2K x 2K active detector. The NFI was developed under NASA sponsorship specifically to track how the Sun's atmosphere evolves into the space environment.

"The launch and deployment of NRL's Narrow Field Imager aboard the PUNCH mission marks a significant step forward in our ability to understand the dynamic processes that drive space weather," said NRL Coronal and Heliospheric Physics Section Head Robin Colaninno, Ph.D. "By imaging the transition of the Sun's atmosphere to the solar wind, we're gaining crucial insights that will ultimately improve our ability to predict and mitigate the impacts of these powerful events on Earth and in space."

Understanding space weather's impact, from minor perturbations to severe phenomena like coronal mass ejections (CMEs) and corotating interaction regions (CIRs), demands accurate models of solar wind behavior. These events begin at the Sun but evolve as they traverse the gap between the solar corona and Earth, particularly through a sparsely observed area in the inner heliosphere.

PUNCH will capture the development of CMEs, providing new data on their origins and movement through space. Such information is critical for predicting the Earth-bound consequences of solar activity, which can range from satellite degradation to communication blackouts and widespread power disruptions. Improved forecasting also offers better protection for space-based systems and exploratory missions operating far from Earth.