NASA's Webb Telescope Discovers New Moon Orbiting Uranus

NASA's James Webb Space Telescope has identified a previously unknown moon orbiting Uranus, increasing the planet's known satellites to 29. The discovery was made during observations on February 2, 2025, using the telescope's Near-Infrared Camera (NIRCam).

The newly detected moon, provisionally designated S/2025 U1, is estimated to be approximately six miles (10 kilometers) in diameter. Its small size likely rendered it undetectable by previous missions, including NASA's Voyager 2 flyby nearly four decades ago. The moon orbits about 35,000 miles (56,000 kilometers) from Uranus' center, situated between the orbits of the inner moons Ophelia and Bianca. Its nearly circular orbit suggests it may have formed near its current location.

"It's a small moon but a significant discovery, which is something that even NASA's Voyager 2 spacecraft didn't see during its flyby nearly 40 years ago," said Maryame El Moutamid, a lead scientist in the Solar System Science and Exploration Division at the Southwest Research Institute.

The discovery underscores the complexity of Uranus' inner system. "No other planet has as many small inner moons as Uranus, and their complex interrelationships with the rings hint at a chaotic history that blurs the boundary between a ring system and a system of moons," noted Matthew Tiscareno of the SETI Institute.

The International Astronomical Union will assign an official name to the newly discovered moon, continuing the tradition of naming Uranian moons after characters from the works of Shakespeare and Alexander Pope.