SAN ANTONIO — December 16, 2025 — After less than a year in orbit, the Southwest Research Institute-built PUNCH spacecraft have made major accomplishments, imaging the Sun in context while tracking comets and enormous space weather events as they traveled through the inner solar system. SwRI's Dr. Craig DeForest discussed the achievements of NASA's PUNCH (Polarimeter to Unify the Corona and Heliosphere) mission during a media roundtable at the AGU25 conference on Dec. 16.
"PUNCH imaging gives us a unique view on the pageantry of the planets and reveals the grandeur of our Sun in the cosmos," said DeForest, PUNCH mission principal investigator. "Seeing solar activity sweeping across the moon, planets and even passing comets gives us a sense of place in our solar system. It reminds me of the impact of the blue marble image of the Apollo era, though PUNCH data is more of a golden fishbowl view of our neighborhood in the cosmos. We live here."
Since PUNCH's four small suitcase-sized spacecraft launched on March 11, they have synched up to act as a single virtual instrument 8,000 miles across. In addition to imaging the Sun's outer atmosphere as it transitions into the solar wind, PUNCH has tracked enormous coronal mass ejections flinging solar particles across the sky and washing over the Earth.
"PUNCH can actually show us directly the violence of space weather as clouds of electrons cross the solar system," DeForest said. "Viewing the corona and solar wind as a single system provides a big-picture perspective essential to helping scientists better understand and predict space weather. This forecasting is critical to protecting astronauts, space satellites and electric grid technology from these events."
The SwRI-developed and -led Wide Field Imagers are aboard three of the four PUNCH spacecraft collecting high-resolution images of entire coronal mass ejections (CMEs) in greater detail than previously possible. These instruments are designed to observe the faint, outermost portion of the Sun's atmosphere and solar wind. The PUNCH science team is working to integrate data from its coronagraph, the Narrow Field Imager provided by the Naval Research Laboratory, from aboard the fourth spacecraft into the overall data products.
"The NASA Small Explorer's mission had a bird's-eye view of the CME in early November that lit up skies across the nation with colorful aurora," DeForest said. "And we've discovered some incredible bonus science that PUNCH performs, tracking comets and other objects. We were able to track the third identified interstellar comet 3I/ATLAS as it traveled through the inner solar system while bright sunlight rendered it invisible to other telescopes and space assets."
In what may be the longest continuous observation of a comet to date, PUNCH also monitored Comet SWAN with unprecedented frequency, clearly imaging the object every four minutes for nearly 40 days, from Aug. 25 to Oct. 2. PUNCH is also tracking Comet Lemmon, which made its closest approach to Earth on Oct. 21.
SwRI's Solar System Science and Exploration Division leads the PUNCH mission and operates the four spacecraft from its facilities in Boulder, Colorado. The Boulder division is part of SwRI's Space Sector, based in San Antonio, Texas. The mission is managed by the Explorers Program Office at NASA Goddard Space Flight Center in Greenbelt, Maryland, for the Science Mission Directorate at NASA Headquarters in Washington.
