Interstellar comet 3I/ATLAS has a tail of constant length that indicates continuous release of material. Observações carried out in November 2025 show no gradual reduction in emission, unlike the pattern observed in natural comets. The object, discovered in July 2025 by the ATLAS telescope at Chile, crossed perihelion in October and is now moving away from Sol.
The tail, which is about 100,000 kilometers long, does not exhibit the erratic impulses common near Sol. Telescópios as well as Hubble and James Webb captured images that confirm the uniformity of the structure.
Early activity marks the trajectory of 3I/ATLAS
The comet activated more than 4 astronomical units from Sol. Essa early reaction suggests a composition rich in heat-sensitive volatiles.
Initial observations in July 2025 detected reddish dust coma. The emission of gas and particles began without the spikes expected from solar objects.
Transition from anti-tail to conventional structure
In July and August, the coma lengthened towards Sol, forming a dust plume. Esse trait, initially confused with anti-tail, resulted from accelerated sublimation on the illuminated face.
After perihelion on October 30, 2025, the tail oriented away from Sol. Imagens of Nordic Optical Telescope registered the change in a few days.
The extension remained stable, with the release of H2O ice grains. Modelos explain the phenomenon by particle dynamics under solar pressure.
Space mission observations enhance data
The Psyche probe captured four images in September 2025, 53 million kilometers away. The photos reveal diffuse coma with no apparent fragmentation.
The Perseverance rover, at Marte, recorded the object on October 4. The distance of 30 million kilometers allowed the coma to be seen as a blurred spot.
- MAVEN detected halo of gas and dust in ultraviolet
- ExoMars TGO obtained color images of the coma on October 3
- SOHO monitored the tail during solar conjunction in October
- PUNCH combined exposures to show short stretch
Artificial control hypothesis divides experts
Scientists note the absence of undetected gravitational acceleration. The stability of the tail contrasts with variations in comets like 2I/Borisov.
Researchers propose that regulated emissions imitate technological propulsion. No However, natural processes such as dust ejection by radiation explain the current data.
Studies from 2025 emphasize composition with water and carbon dioxide. Cosmic-ray-aged crust indicates billions of years of interstellar travel.
Tail details reveal unique composition
Dust in the tail includes refractory and volatile grains. Análises spectra show nickel anomaly and bluish color in the core.
Infrared instruments measured stable surface temperature. The release occurs at 33 gigawatts of solar radiation at perihelion.
The multifaceted structure, with four to five jets, was photographed on November 8. Observadores amateurs confirm fanning of tails in different directions.
Proximity to Marte offers close views
On October 2, 2025, Mars Reconnaissance Orbiter captured the comet 30 million kilometers away. The HiRISE camera pointed to the sky, recording fuzzy coma.
The approach allowed us to refine the orbit by a factor of ten. ESA’s Dados improved forecasts for ground-based observations.
The event occurred without risk to the Martian surface. Instrumentos as CaSSIS at TGO provided stereo images of the coma.
Preparations for land approach in December
3I/ATLAS will reach its closest point to Terra on December 19, 2025. Telescópios will point to assess post-perihelion survival.
Expected magnitude below 12 will require highly sensitive equipment. Visibility will occur in the pre-auroral sky until spring 2026.
Missions like Comet Interceptor plan for future interceptions. Current data serves as the basis for instruments for detecting interstellar objects.
