Beyond the habitable zone lies a frozen, ringed neighbor

Space · Published 23 October 2026 Swipe more like this →

In short: We often focus on Proxima b, the potentially habitable neighbor of our nearest star. But a second, more exotic world may be lurking in the shadows: Proxima c. This distant candidate could host some of the most massive rings ever observed in our local cosmic neighborhood.

Proxima Centauri, the star located 4.25 light-years from Earth, is part of a complex triple-star system. While the primary pair, Alpha Centauri A and B, orbit each other every 80 years, Proxima Centauri orbits them on a much longer cycle of more than half a million years. Within this system, astronomers have identified at least one confirmed planet, Proxima b, a super-Earth with 1.27 times the mass of Earth that orbits its star every 11 days. The two primary stars in this dance are also known as Rigil Kentaurus and Toliman. This stellar arrangement makes the Proxima Centauri system a vital laboratory for studying orbital mechanics.

However, evidence has emerged for a second planetary candidate, Proxima c. Unlike the potentially habitable Proxima b, Proxima c is thought to have temperatures similar to Neptune. This distant world may also be accompanied by an extensive ring system, potentially representing some of the largest rings ever seen. Some models even suggest Proxima c sits at the inner edge of a debris disk. This planet's environment is far more frigid than its inner sibling's. Its position near a debris disk adds to its mysterious profile.

Despite the excitement, the existence of Proxima c remains a subject of scientific scrutiny. While a study published in Science Advances bolstered the potential discovery with additional data, researchers like Fabio Del Sordo of the University of Crete emphasize that the signal could still be a mirage. Astronomers have attempted to use various tools to disprove the signal, but while they have failed to debunk it, they maintain a necessary level of skepticism until further certainty is achieved. The initial reports of this candidate world first surfaced in April 2019. This discovery was led by researchers including Mario Damasso from the Astrophysical Observatory of Turin.

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