3I/ATLAS was found by the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) study telescope in Rio Hurtado, Chile, on July 1, 2025.

Till September, finding out the area and trajectory of the interstellar comet depended on Earth-based telescopes.

In between October 1 and 7, TGO turned its eyes towards 3I/ATLAS from its orbit around Mars.

The comet passed fairly near to Mars, approaching to about 29 million km throughout its closest stage on October 3.

The Mars probe got about 10 times closer to 3I/ATLAS than telescopes in the world and it observed the comet from a brand-new seeing angle.

The triangulation of the TGO/CaSSIS information with the information from Earth assisted to make the comet’s forecasted course far more precise.

While the researchers at first expected a modest enhancement, the outcome was a remarkable 10-fold leap in precision.

“It was an obstacle to utilize the Mars orbiter’s information to fine-tune an interstellar comet’s course through area,” members of the TGO group stated in a declaration.

“The CaSSIS instrument was developed to point towards the neighboring Martian surface area and take a look at it in high resolution.”

“This time, the video camera was targeted at the skies above Mars to capture the small, remote 3I/ATLAS sweeping by throughout a stellar background.”

Astronomers in the planetary defense group at ESA’s Near-Earth Object Coordination Centre, utilized to figuring out the trajectories of asteroids and comets, needed to represent the spacecraft’s unique area.

“Usually, trajectory observations are made from repaired observatories in the world, and sometimes from a spacecraft in near-Earth orbit, like the NASA/ESA Hubble Space Telescope or the NASA/ESA/CSA James Webb Space Telescope,” the scientists stated.

“The astronomers are well-practiced in considering their area as they identify the future places of things, called ephemeris.”

“This time, the ephemeris of 3I/ATLAS, and in specific the forecast’s accuracy, depended upon accounting for the specific area of TGO: at Mars and in a quick orbit around it.”

“It needed interacting in a combined effort by a number of ESA groups and partners, from flight characteristics to science and instrument groups.”

Obstacles and subtleties that are generally minimal, needed to be taken on to minimize the margins as much as possible, in order to attain the greatest precision possible.”