Boulder, Colorado — Astronomers using the James Webb Space Telescope have discovered a new moon orbiting Uranus, bringing the total known moons of the ice giant to 29. This finding suggests that even more moons may yet be hidden within Uranus’s complex system.

The moon, which is small and measured at about 6 miles (10 kilometers) in diameter, was detected through a set of long-exposure images taken by Webb’s Near-Infrared Camera on February 2. Lead scientist Maryame El Moutamid from the Southwest Research Institute remarked that this discovery is significant, especially since it eluded NASA’s Voyager 2 spacecraft during its flyby nearly 40 years ago.

El Moutamid, who leads a Webb program aimed at studying Uranus’s more obscure rings and inner moons, noted that the new moon, currently designated as S/2025 U1, could provide insights into the structure and dynamics of Uranus’s rings. The connection between the moon and the ring materials is particularly intriguing, as it raises questions about whether they share a common origin, possibly linked to an ancient cosmic event.

The moon’s faintness and the bright glow of Uranus’s rings had previously concealed it from detection by both Voyager 2 and telescopes such as Hubble. The discovery underscores the advanced capabilities of the James Webb Space Telescope, which excels in capturing infrared light and resolving images of distant celestial objects.

As the 14th small moon in the Uranian system, S/2025 U1 orbits at approximately 35,000 miles (56,000 kilometers) from the planet’s center, residing between the known moons Ophelia and Bianca. Its nearly circular orbit suggests that it may have formed in situ, rather than being captured from elsewhere in the solar system.

“Discovering new moons around Uranus helps scientists better understand its complex system,” El Moutamid said. The presence of small moons is crucial to our understanding of how they interact with the rings and their evolutionary histories.

Uranus’s moons all carry names from the works of William Shakespeare and Alexander Pope, and there is no literary title assigned to the newly found moon yet. The International Astronomical Union will be responsible for the official naming once the relevant details are finalized.

Scott Sheppard, an astronomer at the Carnegie Institution for Science, expressed excitement about the discovery, emphasizing the potential for even smaller moons to be detected in the future. He noted that the proximity of these small satellites to Uranus, combined with their faintness, makes them particularly elusive.

Looking forward, El Moutamid’s team aims to delve deeper into the new moon’s orbital characteristics, while also supporting upcoming missions designed to explore Uranus and its rings further. Enhanced understanding of Uranus’s rings and moons not only enriches planetary science but also prepares the ground for future exploration missions planned for the early 2030s, which may include dedicated orbiters and atmospheric probes.