Comet C/2025 R3 (PanSTARRS) reaches its peak visibility in the predawn sky on April 17, offering Northern Hemisphere observers a final opportunity to see it before it vanishes from view.
The comet, discovered in September 2025 by the Pan-STARRS telescopes on Haleakala volcano in Hawaii, has been steadily brightening as it approaches the inner solar system. Based on observations logged in the Comet Observation Database, it has reached an estimated magnitude of +4.7, making it visible to the naked eye under dark sky conditions.
Astronomers note that the human eye can typically see objects as dim as magnitude +6.5 in ideal darkness, placing PanSTARRS within range of unaided viewing — though binoculars or a telescope will enhance the experience by revealing its glowing nucleus and developing tail.
The comet is expected to reach its closest point to the sun — perihelion — on April 19, passing within 0.499 AU (about 75 million kilometers) of our star. This close approach is driving its current brightening trend, but also means it will soon be lost in the sun’s glare.
Following perihelion, PanSTARRS will transition from the Northern to the Southern Hemisphere sky, moving through the constellations of Pisces, Cetus, Eridanus, and Orion as it heads back into deep space. Given its orbital period of approximately 170,000 years, it will not return within the lifespan of anyone alive today.
For the best viewing opportunity, observers should look low in the eastern sky about 90 minutes before sunrise. The comet can be found by locating the Great Square of Pegasus and looking approximately five degrees above its lowest star, Algenib — roughly the width of three middle fingers held at arm’s length.
NASA’s monthly skywatching guide has identified April 17 as potentially the best morning to see the comet, with additional close approach to Earth expected on April 27, when it will approach within 44 million miles — about half the Earth-sun distance.
While the comet may be visible to the unaided eye, experts recommend using 10×50 binoculars to spot its nucleus or employing long-exposure photography to capture details in its tail as it interacts with the solar wind.
How bright will Comet PanSTARRS get?
The comet may reach naked eye visibility of about apparent magnitude +3 around its perihelion passage on April 19, based on current projections.
When is the comet’s closest approach to Earth?
Comet C/2025 R3 (PanSTARRS) will make its closest approach to Earth on April 27, coming within 44 million miles of our planet.
Will this comet be visible again in our lifetimes?
No — with an orbital period of approximately 170,000 years, Comet PanSTARRS will not return within the foreseeable future.