Comet SWAN25F rapidly brightening as it nears the Sun

Comet SWAN25F was discovered on March 29, 2025, by amateur astronomer Michael Mattiazzo using data from the SOHO spacecraft. Official confirmation and designation followed shortly after, with initial observations noted by the Minor Planet Center and other astronomical bodies.

The comet’s green coma, caused by diatomic carbon, is currently visible through small telescopes and binoculars.

As of April 6, the comet’s brightness is between magnitude 8.0 and 8.4, requiring binoculars or telescopes for observation. It is located in the constellation Pegasus, low on the east-northeastern horizon before sunrise.

The comet is expected to reach perihelion on May 1, 2025, at a distance of 0.33 AU from the Sun. Its brightness may peak at magnitude 4 or 5, which could make it visible without optical aid, depending on whether it survives the solar encounter.

Observations indicate a tail over 2 degrees long, with visible jets and breaks pointing to active outgassing. Images captured from Arizona, Austria, and the United Arab Emirates illustrate its visibility across various locations.

The comet has brightened from magnitude 10.6 on April 3 to 8.0 by April 6. Despite this rapid increase, astronomers note that the comet’s survival after perihelion is not guaranteed.

The comet is currently best viewed in the morning sky, with a notable alignment near the star Alpheratz expected around April 13. Observers are advised to use binoculars for better visibility.

If it survives perihelion, Comet SWAN25F may be visible during sunset in early May. Its visibility will depend on how well it withstands solar heat and stress.

The discovery has drawn attention from amateur astronomers, including Al-Khatim Observatory in Abu Dhabi who contributed to tracking efforts, marking a milestone for regional astronomy.

Although the comet could reach brightness levels comparable to stars, the possibility of disintegration remains. Continued observation will determine its potential visibility to the naked eye.

References:

¹ Comet SWAN25F updates – SpaceWeather – April 8, 2025

Reet Kaur

I’m a science journalist and researcher at The Watchers, contributing to the Epicenter edition, where I cover peer-reviewed scientific research and emerging discoveries across Earth and space sciences. With a background in astronomy and a passion for environmental science, I’ve worked in shark and coral conservation in Fiji, conducting reef and shark-behavior research, contributing to mangrove restoration, and earning PADI Open Water and Coral Reef Certifications. I bring a blend of scientific rigor and storytelling to illuminate the discoveries shaping our planet and beyond.

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