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The gas-giant planets in our solar system all have rings, though Saturn’s spectacular array is the best known of the bunch. Researchers at the Institute of Astrophysics of Andalusia have found another ring-around-a-planet, but this time it belongs to the oddball dwarf planet Haumea.

Haumea lives out in the neighborhood of Pluto, our most famous dwarf planet, in an area beyond Neptune’s orbit called the Kuiper Belt. According to NASA, Haumea is roughly the size of Pluto, but it rotates rapidly on its axis. It has an elongated form that makes it closer to a rugby ball than a basketball in shape. The icy dwarf planet takes 284 years to complete its orbit around the sun.

The ring discovery comes from a collaborative effort to observe the dwarf planet when it passed in front of a star in January. Twelve telescopes located at 10 different European observatories took a look during the event. The researchers saw a dimming caused by the main body of the dwarf planet, but also noticed briefer dimmings before and after, which indicates the presence of a dense ring.

“It is the first time a ring has been discovered around a trans-neptunian object, and it shows that the presence of rings could be much more common than was previously thought, in our Solar System as well as in other planetary systems,” says a statement from the Institute of Astrophysics of Andalusia.

Lead researcher José Luis Ortiz suggests the ring could have formed from a collision or from “the dispersal of surface material due to the planet’s high rotational speed.” 

The research team published its findings online Wednesday in the journal Nature under the title “The size, shape, density and ring of the dwarf planet Haumea from a stellar occultation.” 

An animated video shows us what Haumea and its ring might look like: