The James Webb Space Telescope (JWST) continues to bear fruit. Images captured by the floating watchtower revealed a previously unknown moon orbiting Uranus. The discovery, made on February 2, increases the planet’s moon tally to 29.
The moon was easy to miss: It’s only an estimated six miles wide. It’s located about 35,000 miles from Uranus’ center, orbiting the planet’s equatorial plane. The moon has a nearly circular orbit, suggesting it could have formed near its current location.
NASA’s short video below shows the faint speck orbiting its ringed host.
The new moon joins 13 other small moons in Uranus’ orbit. The planet also has five major moons (Miranda, Ariel, Umbriel, Titania and Oberon) and 10 irregular ones. The new moon won’t have a name until one is approved by the International Astronomical Union (IAU).
It was detected using 10 40-minute long-exposure images taken by Webb’s Near-Infrared Camera (NIRCam). A team led by the Southwest Research Institute pored through the telescope’s images to identify it.
“No other planet has as many small inner moons as Uranus, and their complex inter-relationships with the rings hint at a chaotic history that blurs the boundary between a ring system and a system of moons,” Matthew Tiscareno of the SETI Institute wrote. “Moreover, the new moon is smaller and much fainter than the smallest of the previously known inner moons, making it likely that even more complexity remains to be discovered.”
