Tonight Is Your Last Chance

Comet C/2025 R3 (PanSTARRS) will disappear from Northern Hemisphere skies for good after the predawn hours of April 17. According to astronomy media reports, the comet is visible low on the eastern horizon 90 minutes before sunrise — and after its perihelion passage on April 19, it will transition to Southern Hemisphere skies, never to return in our lifetimes.

Why This Comet Matters

The Comet Observation Database records C/2025 R3 at an estimated magnitude of +4.7, bright enough to be spotted with the naked eye from a dark location (the human eye's limit is around +6.5). Use 10×50 binoculars to resolve the glowing nucleus, or long-exposure photography to capture the solar-wind-buffeted tail. As the comet approaches perihelion it will brighten further, but solar glare will increasingly wash it out — making tonight the optimal viewing window.

How to Find It

Find a location with a clear eastern horizon and be in position 90 minutes before sunrise. Locate the Great Square of Pegasus rising in the east, then look five degrees above Algenib — the lowest of the four stars — roughly the width of three fingers held at arm's length.

Origin and Fate

C/2025 R3 was discovered in September 2025 by the Pan-STARRS telescopes near the summit of Haleakala volcano on Maui, Hawaii. It brightened significantly during its dive toward the inner solar system, fueling speculation that it could become a great naked-eye comet of 2026. After perihelion, the comet will trace a path through Pisces, Cetus, Eridanus, and Orion as it recedes from the sun — never to be seen again.