NASA’s James Webb Space Telescope has identified a previously unknown moon orbiting Uranus, increasing the planet’s confirmed satellite count to 29. The discovery was made using the telescope’s Near-Infrared Camera during a targeted observation on February 2, 2025, and officially announced on August 19. The newly discovered object, designated S/2025 U 1, measures approximately 10 kilometers in diameter, making it one of the smallest moons detected around Uranus.
It is located between the orbits of the planet’s inner moons Ophelia and Bianca. The satellite follows a near-circular, equatorial orbit and completes a revolution around Uranus in just under 10 hours. The detection was led by planetary scientist Dr. Maryame El Moutamid at the Southwest Research Institute. Her team used ten long-exposure images, each lasting 40 minutes, to confirm the presence of the object. According to NASA, the moon’s faintness and small size likely contributed to its remaining undetected during previous missions, including the Voyager 2 flyby in 1986.
The discovery comes as part of an ongoing survey of Uranus and its surrounding environment, with scientists aiming to better understand the planet’s intricate system of moons and rings. The inner region around Uranus is densely populated with small satellites, many of which orbit close together and may experience gravitational interactions. NASA officials have stated that S/2025 U 1 meets the criteria for formal classification as a natural satellite.
Webb adds new data on dynamic Uranian system
The object currently holds a provisional designation pending review and naming by the International Astronomical Union, which traditionally names Uranian moons after characters from works by William Shakespeare and Alexander Pope. The Webb telescope’s ability to detect such a faint and compact object demonstrates its effectiveness in extending our knowledge of the outer solar system. Scientists involved in the study plan to conduct follow-up observations to refine the moon’s orbital parameters and physical characteristics.
This latest finding contributes to a more detailed understanding of Uranus’s dynamic satellite system, which remains one of the least explored among the outer planets. It also reinforces the importance of space-based infrared observatories in identifying small bodies that ground-based telescopes and older missions may have missed. The report from Dr. El Moutamid’s team has not yet been peer-reviewed. Additional data from future Webb observations are expected to support the findings and provide new insights into the structure and evolution of Uranus’s moons. – By MENA Newswire News Desk.