Teide Observatory’s TTT3 successfully tracks 3I/ATLAS — an object from another star system — as part of Light Bridges’ COMETHYP24 program
The TTT3 (Two-meter Twin Telescope) has successfully tracked the third confirmed interstellar object passing through our Solar System: 3I/ATLAS = C/2025 N1.
The observation was carried out on the night of July 2, between 21:30 and 23:00 UT, with a 1.5-hour image sequence taken through the Sloan g filter using 50-second exposures. The goal: to improve the object’s astrometry and photometry.
Traveling at over 245,000 km/h in a strongly hyperbolic orbit, 3I/ATLAS is unbound to the Sun, confirming its interstellar origin. With an estimated diameter of around 30 kilometers and a relatively close passage, the object offers a rare and valuable scientific opportunity.
The sky quality from the Teide Observatory during the observation was exceptional, and once again the TTT system demonstrated its ability to track fast, faint targets, placing it among the largest robotic telescopes in the world.
This effort is part of COMETHYP24, a ground-based program led by Light Bridges during 2024 to detect, monitor, and characterize hyperbolic comets and interstellar candidates using the TTT and TST telescopes. The project aims to advance our scientific understanding and prepare for future missions capable of direct exploration.
“Teide Observatory continues to rank among the world’s best sites for astronomical science,” says Dr. Miquel Serra-Ricart, Chief Science Officer at Light Bridges and researcher on leave from the Instituto de Astrofísica de Canarias (IAC). “Thanks to the TTT, we can precisely follow objects from other stars — with the potential to reshape what we know about planetary formation beyond the Solar System. Our collaboration with the IAC Solar System Group is proving extremely fruitful.”
Findings like these reinforce the importance of missions like ESA’s Comet Interceptor, scheduled for launch in 2029. Unlike traditional missions, it will wait at a Lagrange point for a dynamically new — ideally interstellar — object like 3I/ATLAS to enter the Solar System for close-up analysis.
The successful tracking of 3I/ATLAS from the Canary Islands highlights the region’s technological capabilities and strengthens Spain’s role in the global pursuit of interstellar exploration.
