Amateur astronomers Edgar Martín-Blas and Asier Arranz have successfully captured images of the interstellar comet 3I/ATLAS, marking a significant achievement in documenting this rare visitor from beyond our solar system. The comet, officially designated C/2025 N1 (ATLAS), was first detected on July 1, 2025, by the ATLAS system in Chile.
3I/ATLAS is the third known interstellar object to pass through our solar system, traveling at an impressive speed of approximately 68 km/s. Martín-Blas, co-founder of Virtual Voyagers and CEO of Spatial Voyagers, and Arranz, who works at Nvidia, used their personal telescopes to record the comet's journey. Martín-Blas utilized his home telescope, while Arranz employed a Skywatcher 200/1000mm telescope paired with a ZWO 1600MM cooled camera and an HEQ5 equatorial mount. Their detailed images and videos have been shared with the astronomical community, providing valuable data for scientific study.
The nucleus of comet 3I/ATLAS is estimated to be between 0.32 and 5.6 kilometers in diameter. Its closest approach to the Sun, or perihelion, is expected on October 29, 2025, at a distance of approximately 1.36 astronomical units. While its peak brightness is anticipated in October, the comet has already become visible in the night sky during September, offering a celestial spectacle for observers.
Martín-Blas plans further observations in October, aiming to capture images of the comet's CO2 tail as it nears the Sun. However, he noted concerns about increasing light pollution in Burguillos, which could hinder astronomical observations. This issue highlights a broader challenge for astronomers globally, as artificial light at night increasingly impacts the clarity of the night sky.
Recent observations from the James Webb Space Telescope and NASA's SPHEREx observatory have revealed that comet 3I/ATLAS is rich in carbon dioxide and also contains water ice and water vapor. This composition offers clues about the conditions in its home star system and the processes that led to its ejection into interstellar space. The discovery and observation of 3I/ATLAS, alongside previous interstellar objects like 'Oumuamua and Borisov, underscore the dynamic nature of our galaxy and the potential for discovering more such visitors. The Vera C. Rubin Observatory is expected to detect one to two new interstellar objects annually once fully operational, further expanding our understanding of these cosmic travelers.