Quaoar's Potential Discovery: A New Moon?

Astronomers are buzzing with excitement as the peculiar dwarf planet Quaoar may have just revealed a new moon! Recent observations by two dedicated astronomers in California have sparked speculation that this enigmatic object harbors either a second satellite or possibly even a third ring.

The Challenge of Observing Distant Worlds

Seeing Quaoar is no easy feat; like other dwarf planets in our solar system, it’s located light-years away. While some, like Ceres, can be spotted with relative ease, Quaoar often eludes direct observation. Astronomers rely on a technique called stellar occultation, where the dwarf planet passes in front of a distant star, causing a momentary blackout that could reveal hidden satellites or rings.

Behind the Scenes of the Discovery

On June 25, 2025, astronomers Rick Nolthenius and his former student Kirk Bender set up for a stellar occultation at the Monterey Institute for Research in Astronomy. To increase their chances of capturing the event, they began recording four minutes early. Their patience paid off spectacularly when they recorded a brief flicker lasting 1.23 seconds—a sign that a new celestial body might be orbiting Quaoar!

Unraveling the Mystery of Quaoar

Discovered in 2002, Quaoar travels beyond Pluto and takes a staggering 286 Earth years to complete its orbit around the sun. Named after a creation deity from Tongva mythology, this dwarf planet has only one confirmed moon, Weywot, found in 2007. The presence of Quaoar's rings has already challenged astronomers' understanding of how such structures can survive in space.

Is It a Moon or Another Ring?

While the initial excitement leans toward the discovery of a new moon, the astronomers cautiously consider the possibility of a third ring. After observing the occultation for an additional few minutes with no further anomalies, they ruled out other explanations, including the shadow of Weywot.

The 'New' Quaoar Moon: What We Know So Far

If confirmed, this newfound moon could be at least 19 miles wide and might share a special orbital relationship with Quaoar’s outermost ring. However, locating it again may prove challenging since it could only be visible from a specific angle.

A Call to Astronomers Around the World

Nolthenius hopes this discovery will inspire more astronomers—both amateur and professional—to focus on observing Quaoar as it currently passes through a star-rich part of the sky. Occultation events are expected to be rare over the coming centuries.

A Potential Name for the New Discovery?

Should the moon be positively identified, Nolthenius even dreams of naming it after someone significant to him, but is mindful of the guidelines set out by the International Astronomical Union.

The Adventure Continues!

As Nolthenius and Bender pursue further occultation hunts, they aim to observe more than a hundred events this year alone, treating each one as a little microadventure in the thrilling realm of space science.