Researchers have identified a new comet, C/2025 R3 (Pan-STARRS), which may become the 'Great Comet of 2026.' This comet could potentially be visible to the naked eye and is expected to reach its closest point to Earth in less than four months.
Discovery and Characteristics
The comet was discovered on September 8, 2025, in images captured by the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) in Hawaii. It is currently approximately 216 million miles (348 million kilometers) from Earth, located between the orbits of Jupiter and Mars. C/2025 R3 is classified as a long-period comet, likely originating from the Oort cloud, and is estimated to take over 1,000 years to orbit the sun. Its exact orbital pathway and period are still being determined by astronomers.
Approach to Sun and Earth
C/2025 R3 is traveling towards the sun and will reach its perihelion (closest point to the sun) on April 20. At this time, it will be approximately 47.4 million miles (76.3 million km) from the sun, situated between the orbits of Mercury and Venus. One week later, on April 27, the comet will make its closest approach to Earth, coming within 44 million miles (70.8 million km). This distance is over 180 times greater than the distance between Earth and the moon.
Visibility Predictions
Astronomers have varying predictions for the comet's brightness. Some estimate an apparent magnitude of 8, requiring a telescope or binoculars for viewing, while others predict a magnitude of 2.5, which would make it visible to the naked eye. Apparent magnitude is a reverse logarithmic scale where lower numbers indicate greater brightness.
The comet's brightness is influenced by several factors:
- Forward scattering: If the comet is positioned directly between Earth and the sun, its tail may scatter more sunlight, increasing its apparent brightness.
- Solar radiation interaction: As the comet approaches the sun, increased solar radiation causes it to release trapped ice and gases, which then reflect sunlight towards Earth. The exact impact of this phenomenon on C/2025 R3's brightness is not yet known.
Best Viewing Opportunities
The optimal time for viewing C/2025 R3 is expected to be around April 17, just before its perihelion, coinciding with a new moon for darker skies. Viewers in the Southern Hemisphere may also have good viewing opportunities in early May. During its closest approach to the sun and Earth, the comet will be located in the constellation Pisces, below the Great Square of Pegasus.
Potential as the 'Great Comet of 2026'
With few other significant comets predicted for 2026, C/2025 R3 is considered a strong candidate for the "Great Comet" title, typically given to the brightest comet of a given year. However, there remains a possibility that another brighter comet could be discovered later in the year.