The interstellar celestial body known as 3I/Atlas recently reached its closest point to Sol, an event that triggered intense physical reactions on its surface and provided unprecedented data on the chemical composition of objects formed in the early days of the galaxy. Detectado initially in July last year through a monitoring system located at Chile, the object traveled through deep space until it crossed the inner region of our planetary system. Durante perihelion, extreme thermal radiation caused the rupture of a thick outer layer that sealed the object’s core billions of years ago. Essa structural degradation has allowed space and ground-based observatories to record the eruption of volatile compounds that have remained frozen and protected from degradation in the vacuum of deep space for eons. Immediate spectroscopic analysis confirmed the presence of elements fundamental to organic chemistry, ejected through high-speed directional jets. The astronomical event gains relevance due to the estimated age of the celestial body, which carries unchanged materials from a time before the formation of our planetary neighborhood.
Origin in the thick disk of Via Láctea
Astrometric calculations based on the hyperbolic trajectory of 3I/Atlas indicate that its estimated age varies between ten and twelve billion years. Essa dating places the origin of the object in a primordial phase of the galaxy, long before the condensation of the molecular cloud that gave rise to Sol and the local planets.
The traced source points to the thick galactic disk, a vast region characterized by the presence of old stars and significantly lower metallicity. The materials preserved inside the cometary nucleus function as a chemical time capsule, offering direct samples of the environmental conditions of this remote era.
The thermal insulation provided by the interstellar medium ensured that the original molecules did not undergo significant changes through sublimation throughout their journey. The absence of nearby stars for most of its existence prevented early warming of the primordial ice, allowing astronomers to investigate the nucleosynthesis processes and cosmic dust formation that occurred in the first tens of millions of years after the formation of Via Láctea.
Dynamics of surface crust rupture
The surface of the celestial body has developed a hardened crust about twenty meters thick, the result of the continuous bombardment of galactic cosmic rays during their transit through the interstellar medium. Long exposure to high-energy radiation altered the molecular structure of the outermost layers, creating a dense natural polymer that acted as a highly effective thermal barrier against mass loss. The mechanical resistance of this crust prevented the release of volatile gases even when the object began to cross the orbit of the gas planets in our system, maintaining internal pressure at the physical limit of the material.
The collapse of this protective structure occurred only after months of gradual solar warming, when the temperature differential between the surface and interior exceeded the cohesive strength of the altered ice. The rupture caused an explosive and asymmetric release of material, generating a non-gravitational acceleration that subtly modified the body’s orbital parameters. The rapid expansion of the coma, which reached hundreds of thousands of kilometers in diameter, revealed sublimation dynamics completely different from those observed in comets originating from the Nuvem of Oort or the Kuiper belt.
Chemical signatures of organic molecules
The fragmentation of the crust exposed anomalous concentrations of methanol, exceeding the average levels documented on native celestial bodies by up to four times. Observações at millimeter wavelengths confirmed that the emission of this alcohol occurred in specific peaks, synchronized with the rotation of the nucleus and the exposure of the fissures to solar heat.
The spectrometers also detected the presence of hydrocyanic acid, water, carbonyl sulfide and several allotropic forms of carbon, in addition to methanol. The simultaneous detection of these elements reinforces the thesis that complex chemical reactions can occur on the surface of dust grains in cold molecular clouds.
Traces of ionized nickel were also identified in the inner coma, adding a rare inorganic component to the emission profile. The mixture of these volatile compounds demonstrates the richness of material available for the synthesis of organic precursors in primordial stellar environments.
The intact preservation of these organic and inorganic elements for billions of years in deep space provides concrete evidence about the universal distribution of the chemical building blocks necessary for the formation of complex planetary systems.
Gravitational interaction in the Jovian orbit
The object’s route included a strategic passage through the vicinity of Júpiter on March 16, 2026, reaching a minimum distance of zero point three hundred and fifty-eight astronomical units from the gas giant. The celestial body quickly crossed the planet’s Hill sphere and was subjected to tidal forces that, although measurable, were not enough to cause the disintegration of the main core.
The gravity of Júpiter caused millimetric deviations in the hyperbolic trajectory, insufficient to capture the visitor in a closed orbit. The speed maintained at the mark of sixty-eight kilometers per second in relation to the Sol provided the kinetic energy necessary for its definitive escape route towards the limits of the planetary system.
Monitoring by telescope networks
The observation campaign mobilized unprecedented global and space infrastructure to record each phase of the comet’s activity during closest approach. The James Webb space telescope used its mid-infrared instruments to map the thermal distribution of the ejected dust, while the ALMA observatory, located in the Atacama desert, focused on detecting the rotational transitions of cold gas molecules in the outer coma. Simultaneamente, the instrument telescope of the Juice mission, which is en route to the Jovian system, was calibrated to capture the ultraviolet spectra of the event, complementing terrestrial data and establishing a three-dimensional model of the sublimation rate of different chemical compounds under extreme irradiation conditions. Coordination between these different observation platforms has allowed the collection of a massive volume of raw data that will continue to be processed by astronomical research centers in the coming months, ensuring a complete mapping of the chemical composition of the interstellar visitor.
Core morphology and directional jets
Photometric analysis revealed that the nucleus has a markedly elongated shape and a slow rotation rate, which gradually exposes different hemispheres to radiation. Essa irregular geometry is responsible for the intermittent activation of jets of carbon dioxide and carbon monoxide, which drag with them large amounts of silicate dust into the surrounding space.
The proportion of water detected in the emissions was lower than the average for our planetary system, indicating a distinct proportion of dust and ice. Essa morphological and compositional characteristic serves as a new reference standard for the classification of future interstellar bodies that may transit through our vicinity.
Escape route to deep space
Free from the gravitational influence of the giant planets, the celestial body now follows a straight trajectory towards the limits of the heliosphere. As surface temperatures drop, sublimation activity will progressively decrease, and the object will return to its original dormant state for another billion-year journey into the interstellar void.