China’s Tianwen 1 Mars probe has provided the world with an unexpected bonus: stunning images of interstellar comet 3I/ATLAS as it zipped past our solar system’s neighborhood in early October. This glimpse into a visitor from beyond helps scientists unravel the mysteries of these rare celestial wanderers.
3I/ATLAS is only the third known object to have journeyed into our solar system after originating in another star system. Its predecessors, ‘Oumuamua in 2017 and 2I/Borisov in 2019, sent ripples through the scientific community, raising questions about the composition of distant planetary systems and how objects can navigate interstellar space. With its arrival, global space agencies scrambled to capitalize on this rare opportunity for observation.
The European Space Agency and NASA directed their Mars missions—including orbiting spacecraft and surface rovers—toward 3I/ATLAS as it swept past in early October. Now, the China National Space Administration (CNSA) has joined the chorus of celestial watchers. They’ve released images captured by Tianwen 1 between October 1st and 4th, showcasing the comet’s path across the backdrop of distant stars. A standout image from October 3rd reveals the comet in striking detail.
Tianwen 1 utilized its High-Resolution Imaging Camera (HiRIC) to capture these remarkable images. While comparable in function to NASA’s Mars Reconnaissance Orbiter’s HiRISE instrument, HiRIC boasts slightly lower resolution. The challenge for capturing this fleeting visitor was immense: shifting focus from the bright, detailed landscapes of Mars to tracking a faint object moving at an astonishing speed of 129,800 mph (58 km per second) while positioned 18 million miles (28.96 million kilometers) away.
The comet itself appears as a celestial ballet dancer in the images: a compact nucleus encircled by a hazy, glowing coma extending several thousand kilometers into space—evidence of gas and dust evaporating from its sun-warmed surface. According to CNSA’s official statement on November 5th, “Data acquired by a high-resolution camera was received, processed and displayed by a ground-based application system.” This feat not only provided valuable data about 3I/ATLAS but also offered practical training for future deep-space endeavors.
This interstellar encounter represents a crucial extension mission for Tianwen 1. The ability to spot such faint celestial bodies provides vital testing grounds for the technological challenges inherent in exploring even more distant cosmic targets. The experience gained will undoubtedly be invaluable as China prepares for its next ambitious space venture—the Tianwen 2 mission, currently en route to sample a near-Earth asteroid.
