An international team of professional astronomers and amateur observers has confirmed the existence of an extremely thin atmosphere around the trans-Neptunian object 2002 XV93. The discovery, published in the journal Nature Astronomy, marks the first time that an atmosphere has been confirmed on a celestial body of this type other than Plutão, revolutionizing the understanding of these distant worlds.
The object, located approximately 37 astronomical units from Terra, about 5.5 billion kilometers, defied scientific expectations. With a diameter of around 500 kilometers, the celestial body has such weak surface gravity that theoretically it would not be able to maintain an atmosphere for long periods.
Revolutionary Método detects imperceptible changes
The team led by Professor Wataru Arimatsu of Observatório Astronômico Nacional of Japão used the phenomenon of stellar occultation to make the discovery. Durante this occultation, on January 10, 2024, the trans-Neptunian object passed in front of a distant star, temporarily obscuring its light. Observadores in three Japanese prefectures, Kyoto, Nagano and Fukushima, simultaneously captured the event using professional telescopes and amateur equipment.
The Tomo-e Gozen instrument, mounted on Schmidt’s Observatório Kiso’s Universidade’s 105-centimeter telescope, recorded crucial data. The gradual change in the star’s brightness revealed something extraordinary: the light progressively dimmed and then gradually recovered. Esse pattern can only occur when light is refracted by an atmosphere. Sem atmosphere, the star would disappear and reappear instantly.
Bare Atmosphere Características
Detailed data analysis confirmed that 2002 XV93 has an extremely tenuous atmosphere with pressure between 100 and 200 nanobars. Para For comparison purposes, this pressure corresponds to just one ten-millionth of the atmospheric pressure on the surface of Terra.
The discovery surprised the scientific community because:
- Nenhum, another trans-Neptunian object besides Plutão, had previously confirmed an atmosphere.
- Corpos much larger celestial bodies, such as Éris and Makemake, with diameters between 1000 and 2000 kilometers, did not show clear evidence of an atmosphere
- The theory predicted the impossibility of retaining gases in bodies so small and distant
- Extremely low pressure suggests unstable, short-lived atmosphere
Possíveis atmosphere origins detected
Cientistas point to two main hypotheses to explain how 2002 XV93 acquired its atmosphere. The first suggests the release of gases from the interior of the celestial body related to volatile substances, equivalent to very low temperature volcanic activity. The second possibility is a relatively recent collision with a small celestial body that would have released volatile material into the surrounding space.
Ambas explanations indicate that trans-Neptunian objects are not completely inactive worlds, as previously believed. The impact of this discovery goes beyond numbers: it redesigns scientific understanding of geological and atmospheric dynamics in extreme regions of the solar system.
Colaboração between professionals and amateurs
The success of the observation crucially depended on collaboration between professional astronomers and amateur observers. Essa partnership allowed simultaneous geographic coverage at multiple points, essential for confirming the atmospheric refraction pattern. The data obtained from Nagano and Fukushima were consistent, reinforcing the conclusion that the atmosphere is real.
Professor Arimatsu described the results as “a discovery that overturns conventional views.” The researcher highlighted the importance of continuing to investigate other trans-Neptunian objects to determine whether more celestial bodies have atmospheres and better understand the processes that generate them.
Futuro from observations of the distant solar system
Próximas observations with Telescópio Espacial James Webb should shed additional light on the properties of trans-Neptunian objects, including the chemical composition of their atmospheres and formation processes. The research team plans to expand the mobile observation program to systematically investigate the presence or absence of atmospheres on other celestial bodies in this region.
The 2002 discovery of XV93 opens a new chapter in planetary astronomy. Sugere that distant, seemingly inert worlds may possess unexpected dynamic activity, fundamentally altering how scientists think about evolution and characteristics of small bodies in extreme orbits around Sol.
