Astronomers Detect Thin Atmosphere Around Distant Kuiper Belt Object Beyond Pluto

Astronomers detected a thin atmosphere around the object (612533) 2002 XV93 using three telescopes in Japan. The object, 300 miles (500 kilometers) across, is located beyond Pluto in the Kuiper Belt and classified as a plutino. A plutino circles the sun twice in the time it takes Neptune to complete three solar orbits.

5 billion kilometers) away from Earth, farther than Pluto. Pluto is the only other object in the Kuiper Belt with an observed atmosphere. The atmosphere of (612533) 2002 XV93 is 5 million to 10 million times thinner than Earth's atmosphere and 50 to 100 times thinner than Pluto's atmosphere.

The study was published in the journal Nature Astronomy on Monday. Researchers observed (612533) 2002 XV93 in 2024 as it passed in front of a background star, with the observation occurring on January 10, 2024, according to lead researcher Ko Arimatsu. The telescopes were located in Kyoto, Nagano Prefecture, and Fukushima in Japan.

5 seconds near the edge of the shadow, Ko Arimatsu said. The surface pressure of the atmosphere on (612533) 2002 XV93 is about 100 to 200 nanobars, according to Arimatsu. Ko Arimatsu is an associate professor at the National Astronomical Observatory of Japan.

"This is an amazing development, but it sorely needs independent verification. The implications are profound if verified," said Alan Stern, the lead scientist behind NASA's New Horizons mission to Pluto and beyond, who works at Southwest Research Institute and was not involved in the study.

"It changes our view of small worlds in the solar system, not only beyond Neptune," Arimatsu said in an email.

The object (612533) 2002 XV93 has a diameter of 311 miles (500 kilometers), while Pluto has a diameter of 1,477 miles (2,377 kilometers). 5 billion years ago. The object (612533) 2002 XV93 was discovered nearly a quarter of a century ago.

"This was an exciting discovery to read about," said Scott S. Sheppard, a staff scientist at the Carnegie Institution for Science in Washington, DC, who did not participate in the research. " Sheppard noted the finding highlights recent activity on (612533) 2002 XV93, whether from the eruption of frozen gases or material from a collision.

"This shows the Kuiper Belt is not a cold dead place, but is teeming with activity and has many of the building blocks for life," Sheppard said in an email. Jose-Luis Ortiz, a Spanish astronomer who studies dwarf planets beyond Neptune and was not involved in the research, said the results were interesting but urged caution. "I still doubt that it is an atmosphere.

We need more data," Ortiz told AFP. The likeliest atmospheric chemicals are methane, nitrogen or carbon monoxide, according to Arimatsu. Further observations, especially by NASA's Webb Space Telescope, could verify the makeup of the atmosphere.

"That is why future monitoring is so important," Arimatsu said. "If the atmosphere fades over the next several years, that would support an impact origin. If it persists, or varies seasonally, that would point more toward ongoing internal gas supply" from ice volcanoes.

Arimatsu acknowledged that he could not rule out "exotic alternatives" to an atmosphere, such as a ring close to the body. However, "a nearly edge-on ring does not seem consistent with the main features of our observations," he added. The discovery could offer an unprecedented glimpse into how an atmosphere forms and remains around a small object, changing how astronomers think about objects in the Kuiper Belt.