New Moon Discovered Orbiting Uranus Using NASA’s Webb Telescope
We’re not sitting on this one, Uranus has another Moon!
Webb discovered an unknown moon orbiting the planet, expanding its known satellite family to 29. The newly discovered moon is estimated to be just six miles (10 km) in diameter, assuming it has a similar reflectivity (albedo) to Uranus’ other small satellites. We haven’t seen this moon before now, likely due to its small size rendering it invisible to earlier missions or telescopes.
Of the planet's now 29 moons, this one is the 14th member of the system of moons orbiting inward of the largest moons, Miranda, Ariel, Umbriel, Titania, and Oberon.
Read the full story: science.nasa.gov/blogs/webb/2025/08/19/new-moon-discovere...
Credits: NASA, ESA, CSA, STScI, M. El Moutamid (SwRI), M. Hedman (University of Idaho)
Image description: An image titled “James Webb Space Telescope, Uranus, Discovery of Moon S 2025 U1”. At center is the planet Uranus, a blue globe with a large white spot occupying most of the planet. It’s surrounded by a series of rings that get brighter as you move outward. Beyond the rings are 14 labeled moons appearing as points of light. Just beyond the outermost ring at 10 o’clock, a faint moon is circled and labeled S 2025 U1. At far left, the brightest moon is labeled Miranda. Additional moons clockwise from Miranda are Puck, Cressida, Mab, Perdita, Desdemona, Belinda, Bianca, Ophelia, Rosalind, Portia, Cupid, and Juliet. At lower right are compass arrows with east pointing to 11 o’clock and north pointing to 2 o’clock. At bottom, a label reads NIRCam F150W2.
New Moon Discovered Orbiting Uranus Using NASA’s Webb Telescope
We’re not sitting on this one, Uranus has another Moon!
Webb discovered an unknown moon orbiting the planet, expanding its known satellite family to 29. The newly discovered moon is estimated to be just six miles (10 km) in diameter, assuming it has a similar reflectivity (albedo) to Uranus’ other small satellites. We haven’t seen this moon before now, likely due to its small size rendering it invisible to earlier missions or telescopes.
Of the planet's now 29 moons, this one is the 14th member of the system of moons orbiting inward of the largest moons, Miranda, Ariel, Umbriel, Titania, and Oberon.
Read the full story: science.nasa.gov/blogs/webb/2025/08/19/new-moon-discovere...
Credits: NASA, ESA, CSA, STScI, M. El Moutamid (SwRI), M. Hedman (University of Idaho)
Image description: An image titled “James Webb Space Telescope, Uranus, Discovery of Moon S 2025 U1”. At center is the planet Uranus, a blue globe with a large white spot occupying most of the planet. It’s surrounded by a series of rings that get brighter as you move outward. Beyond the rings are 14 labeled moons appearing as points of light. Just beyond the outermost ring at 10 o’clock, a faint moon is circled and labeled S 2025 U1. At far left, the brightest moon is labeled Miranda. Additional moons clockwise from Miranda are Puck, Cressida, Mab, Perdita, Desdemona, Belinda, Bianca, Ophelia, Rosalind, Portia, Cupid, and Juliet. At lower right are compass arrows with east pointing to 11 o’clock and north pointing to 2 o’clock. At bottom, a label reads NIRCam F150W2.