European Mars Orbiters Capture Interstellar Comet 3I/ATLAS Near Mars

European Mars Orbiter Spies Interstellar Comet 3I/ATLAS

In a rare celestial event, the European Space Agency’s ExoMars Trace Gas Orbiter and Mars Express missions captured images of interstellar comet 3I/ATLAS as it sped past Mars on October 3, 2025. These orbiters, normally focused on studying the Martian surface, had to adapt quickly to observe a faint, distant visitor—a testament to the flexibility and ingenuity of modern space exploration. The comet appeared as a fuzzy white dot moving through the Martian sky, with its icy nucleus and surrounding coma just barely visible. Observing such a dim object from millions of kilometers away was a significant technical challenge, but the effort paid off with unique data about this mysterious interloper from beyond our solar system.

Why This Observation Matters

Though Mars orbiters are designed for planetary science, their ability to pivot and observe unexpected deep-space phenomena adds exciting new capabilities to their mission profiles. The images of 3I/ATLAS, though low-resolution, provide valuable insights into the comet’s activity as it approaches the Sun, with its coma stretching thousands of kilometers. As the comet continues its journey, future observations may reveal a growing tail, offering clues about the composition and behavior of interstellar objects. This serendipitous encounter highlights how even routine planetary missions can contribute to broader astronomical discovery, turning Mars orbiters into unexpected eyes on the cosmos.