Comets are known for their fleeting, brilliant displays in our night sky. Recently, one comet, C/2025 R2 (SWAN), caught NASA’s attention like never before. For almost 40 days, NASA’s PUNCH mission took pictures of this comet every four minutes. This intense observation is possibly the longest and closest tracking of a comet, as noted in a NASA announcement.
Craig DeForest, the principal investigator for the PUNCH mission at the Southwest Research Institute, emphasized that previous comets have only been monitored once a day. “This frequent observation is a game changer,” he explained.
Comet C/2025 R2 (SWAN) was first spotted in September by Ukrainian amateur astronomer Vladimir Bezugly. He noticed it in images from the Solar and Heliospheric Observatory (SOHO), a spacecraft that monitors the sun. Just a day after its discovery, the comet made its closest pass to the sun, coming within 46.74 million miles.
Initial images revealed a bluish-green coma, a cloud of gas and dust forming as the sun heated the comet’s ice. This process, called sublimation, created a glowing tail that scientists frequently analyze. By mid-September, the coma had a peculiar triangular shape, often seen in comets that are breaking apart.
Interestingly, SWAN and another interstellar visitor, 3I/ATLAS, shared the same section of the sky. In timelapse videos from PUNCH, 3I/ATLAS appears momentarily, zooming by beneath SWAN.
The comet’s tail is influenced by solar wind, making it appear to drift in the opposite direction. This dynamic shows how the sun affects comets as they move through our solar system.
According to Gina DiBraccio from NASA, watching the sun’s effects on comets helps us understand how space weather impacts our technology and astronauts. “Our tools let us track and analyze these interactions effectively,” she said.
In late October, C/2025 R2 (SWAN) came within 25.1 million miles of Earth, nearing the threshold for naked-eye visibility. Binoculars or small telescopes could easily spot it, making it an exciting event for amateur astronomers.
As we gaze at these cosmic visitors, remarkable improvements in technology continue to deepen our understanding of them. The PUNCH mission underscores the potential for future discoveries. With constant advancements in space observation, who knows what we might uncover next?
For more information about comets and their behavior, you can check out the NASA website.
