NASA’s PUNCH Watches Comet Lemmon Respond to the Sun’s Powerful Influence

As Comet Lemmon brightened while swooping through the Sun's neighborhood in late 2025, images recorded by NASA's PUNCH mission revealed rare views of how solar forces shape a comet moments before it is pulled apart. From orbit around Earth, the mission witnessed as the comet traversed its vast field of view, providing a moving waypost of solar wind activity. The images reveal subtle and dramatic changes in the comet's tail as charged particles from the Sun streamed outward, offering scientists a clearer picture of how solar behaviour affects objects across the inner solar system.

PUNCH Movie Shows Solar Wind Distorting Comet Lemmon's Tail

According to a NASA report, the findings were summed together to create a movie of snapshots taken between Oct. 22 and Nov. 12, 2025, capturing Comet Lemmon as it moved in front of background stars and its tail transiently changed shape. Differences in the solar wind had caused the tail to grow longer, shorter, and even snap temporarily. More solar activity on November 1 and November 4, stronger solar activity appeared to disrupt the tail, which later regrew as conditions settled.

Discovered in January 2025, the comet entered PUNCH's view in October, giving scientists a rare chance to study solar wind–comet interactions.

PUNCH Tracks Comet Lemmon as Solar Wind Actively Reshapes Its Fading Tail

PUNCH's four small spacecraft continuously observe the region where the Sun's outer atmosphere transitions into the solar wind. By watching Comet Lemmon move through this environment, researchers could directly see how solar particles push and reshape a comet's tail over time.
Though still visible in PUNCH data, Comet Lemmon is fading and is expected to leave the spacecraft's view by mid-January 2026.