Uranus's small moons are dark, red, and water

This article was originally published at Eos. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

The solar system's oddball planet has some pretty odd moons, too. The first infrared spectra of Uranus's small inner moons, which will be presented on 18 December at the 2025 AGU Annual Meeting in New Orleans, have shown that their surfaces are much redder, much darker, and more water-poor than the larger moons orbiting far from the planet.

"We were trying to see how these properties varied across the rings and moons," said Matt Hedman, a planetary scientist at the University of Idaho in Moscow and a coauthor on the research. "We didn't have a lot of information about their spectra before because they’re hard to observe."

The new observations also reveale