The interstellar comet 3I/Atlas, discovered in July 2025, had the growth of its tail recorded by robotic telescopes at Projeto Telescópio Virtual, at Itália. As images, taken on November 11, show the comet’s ionic tail sharper, extending 0.7 degrees in a northeasterly direction. The observation occurred after perihelion, the point of closest approach to Sol, on October 29. The phenomenon is attributed to the sublimation of gases, intensified by solar heat.
The ARTEC250+Paramount ME+C3Pro61000EC robotic unit was essential for the capture. As images also reveal an antitail, facing east-southeast, visible from Terra’s perspective. The Observatório Astronômico Bellatrix highlighted the sharpness of the photos. The comet, which does not pose a risk to Terra, follows a hyperbolic trajectory, indicating an origin outside of Sistema Solar.
- The ionic tail grew due to the release of gases and dust.
- The antitail is an optical effect, common in comets close to perihelion.
- 3I/Atlas is the third interstellar object identified, after Oumuamua and Borisov.
New images detail the structure of the comet
The November 11 photos show the bright core of 3I/Atlas. The longer tail reflects greater comet activity.
The sublimation of ice, like carbon dioxide, forms the coma, a gaseous cloud around the nucleus. Astrônomos estimate that the core is between 320 meters and 5.6 kilometers in diameter.
Real-time observation
Projeto Telescópio Virtual announced a live stream on YouTube. The live, scheduled for November 19, at 1:15 am (Brasília time), will show the comet in real time.
The initiative, led by Gianluca Masi, brings together remotely controlled robotic telescopes. The broadcast aims to engage the public and detail recent discoveries.
Interstellar comet intrigues scientists
3I/Atlas was detected by the Atlas telescope, on Chile. Sua’s trajectory suggests that it is older than Sistema Solar, at about 7.6 billion years old.
The composition, rich in carbon dioxide, is unusual. Dados of Telescópio Espacial James Webb indicate eight times more CO₂ than water in the coma.
The comet moves at 221 thousand km/h, with no risk of collision with Terra. In March 2026, it will reach 50 million kilometers of Júpiter.
Technology behind the images
The ARTEC250 unit captured images with high precision. The equipment is optimized for fast-moving objects.
Telescopes such as Gemini South and Hubble also observed the comet. Suas images complement the data from Projeto Telescópio Virtual.
The combination of technologies makes it possible to study the chemical composition. Isso helps understand the formation of distant planetary systems.
The lack of fragmentation after perihelion surprised scientists. The comet maintains integrity by continually releasing material.
Scientific importance of 3I/Atlas
3I/Atlas offers clues about distant star systems. Sua passage is a rare opportunity for astronomy.
Continuous monitoring
Rede Internacional of Alerta of Asteroides monitors the comet. Um training, from November 2025 to January 2026, will refine orbital measurements.
