Astronomers record new images of comet 3I/ATLAS on December 26, 2025. The object, the third confirmed object of interstellar origin, moves away from Sistema Solar on a hyperbolic trajectory. Descoberto in July 2025 by the ATLAS system in Chile, the comet passed closest to Terra on December 19, at about 270 million kilometers.
The comet presents typical activity, with a coma and tail, but a different composition of objects than Sistema Solar. Recent Observações highlight brightness in X-rays and green tones in the tail.
- Distance from Terra: approximately 1.82 AU.
- Distance from Sol: about 2.5 AU.
- Apparent magnitude: around 13, requiring telescopes for viewing.
- Position in the sky: in the constellation of Leão.
Discovery and trajectory of the object
Comet 3I/ATLAS was identified on July 1, 2025. Sua hyperbolic orbit confirmed origin outside of Sistema Solar, making it the third known interstellar object, after 1I/’Oumuamua in 2017 and 2I/Borisov in 2019.
It reached perihelion on October 29, 2025, at 1.36 AU from Sol. Após passing through the solar conjunction, it became visible again in November.
The speed relative to Sol reaches 64 km/s, guaranteeing that it will not return.
Composition revealed by observations
Telescopes such as James Webb and Hubble have detected abundant carbon dioxide, as well as carbon monoxide, water vapor and carbonyl sulfide.
X-ray observations by ESA’s XMM-Newton showed brightness caused by the interaction of gases with the solar wind.
Images from Gemini North revealed a greenish coma, typical of gaseous emissions.
These data indicate formation in a distant region of another star system.
Recent activity and images
The comet displayed a bluish plasma tail in December photos. Missões as Parker Solar Probe captured images during a difficult period for Earth observation.
Spacecraft such as Psyche, MAVEN and Europa Clipper contributed ultraviolet and dust data.
Activity remained stable, without significant fragmentation.
Current position and observation
On December 26, 2025, the comet is located at Leão, visible before dawn with suitable equipment.
Its 13th magnitude makes it a target for amateur tracking telescopes.
It will cross Júpiter orbit in 2026, but without a close approach.
Scientific importance of the visitor
3I/ATLAS offers a rare opportunity to study material from another star system. Sua estimated age may exceed billions of years.
Observations coordinated by NASA and ESA continue to process data for composition models.
The object reinforces estimates that interstellar visitors regularly pass through Sistema Solar.
Future trajectory
The comet heads into interstellar space, crossing the orbits of outer planets over the next few years.
He poses no risk and stays away permanently.
Data collected will be used for long-term studies of interstellar objects.