Agência Espacial Europeia’s JUICE probe recorded an extraordinary discovery when observing the interstellar comet 3I/ATLAS in February 2026. The celestial object expelled water vapor in a volume equivalent to approximately 70 Olympic-sized swimming pools daily. Scientific instruments captured data revealing the release of about two tons of material per second during the interstellar visitor’s passage through Sistema Solar.
JUICE’s Detectores reveals unexpected comet activity
The JUICE mission, heading toward Júpiter, had the unique opportunity to observe 3I/ATLAS as operators adjusted instruments during narrow time windows. Cinco scientific equipment was activated simultaneously to capture data from the comet. The thermal environment required special care with the supercooled cameras, but the ESA team judged that the operational risks were worth the rare opportunity.
The MAJIS spectrometer recorded infrared emissions of water vapor and carbon dioxide emanating from the core. The JANUS camera captured detailed images showing an extensive coma with structures like jets and filaments of gas. NavCam assisted in accurate trajectory tracking from angles not accessible to ground-based telescopes, providing unique perspectives on the object’s movement.
Características notable cometary activity recorded
- The comet released water even at distances greater than Earth’s orbit.
- Significant Parte material evaporated from icy dust grains on the side illuminated by Sol.
- The activity continued intensely after perihelion, surprising astronomers.
- Observações on different filters revealed variations in dust and gas distribution.
- The data allowed us to accurately estimate the outflow from the cometary nucleus.
The observation opportunity arose by chance, but it demonstrated the importance of keeping scientific instruments ready for unexpected targets. The probe was in the right position at the right time, allowing scientists to collect information that would otherwise have been impossible to obtain.
Ancient Origem and Distinctive Interstellar Visitor Composition
Estimativas indicate that 3I/ATLAS formed more than 10 billion years ago in another star system, making it a cosmic relic of distant origin. The ratio between light and semi-heavy water detected by the instruments reveals an extremely cold formation environment with intense ultraviolet radiation. Astrônomos had previously detected hydroxyl using NASA’s Observatório Neil Gehrels Swift in October 2025, when the comet was expelling about 40 kilograms of water per second at three times the Terra-Sun distance.
Water didn’t just come out of the comet’s solid core. Grande part evaporated from a fragile cloud of grains surrounding the nucleus, explaining the extraordinary intensity of the emission. Esse phenomenon occurred earlier than expected for typical Sistema Solar comets, suggesting volatile ices buried beneath the surface that were released by solar heating.
Detailed Imagens reveals complex cometary structure
The JANUS camera recorded the comet from tens of millions of kilometers away, capturing a bright green coma caused by the emitted gases. The tails extended millions of kilometers into space, creating a stunning visual structure. Different Filtros highlighted variations in the distribution of dust and gas, with a color image showing the compact center and diffuse structures around it.
The ultraviolet spectrograph detected elements that extended up to 5 million kilometers from the core. Essas observations help scientists understand how released material affects the comet’s trajectory through space. Pequenas changes in dust and gas release significantly influence the orbital path, crucial data for planetary defense calculations and modeling of icy bodies.
Implicações for understanding distant star systems
The volume of water released by 3I/ATLAS surprised the scientific team, as common comets show lower rates of material loss close to Sol. The abundant presence of water in an interstellar object reinforces that chemical ingredients essential for life appear widely in other stellar systems. The JUICE probe continues to analyze data to understand the comet’s evolution after perihelion, with the main mission continuing to the moons of Júpiter with arrival scheduled for 2031.
3I/ATLAS is the third confirmed interstellar object, after 1I/ʻOumuamua and 2I/Borisov, each bringing different surprises in the composition. Telescópios terrestrials had difficulty during the solar conjunction, but JUICE’s privileged position allowed for a unique view of the phenomenon. Complementary Dados Observatório Swift, the Subaru telescope and other observatories complete the scientific picture, contributing to future research on icy bodies and planetary formation in distant cosmic environments.