The interstellar object known as 3I/ATLAS has captured the attention of astronomers since its detection on July 1, 2025, by the Asteroid Terrestrial-impact Last Alert System (ATLAS) at the Las Armas Observatory in Chile. Recent studies suggest that this extraordinary object could be older than our Solar System, potentially reshaping our understanding of cometary origins.
3I/ATLAS is unique as it follows a hyperbolic orbit, meaning it is not bound by the Sun’s gravity. Instead, it traverses the space around our star, moving at an impressive velocity of approximately 58 km/s (about 130,000 mph). This speed and trajectory indicate an interstellar origin, setting it apart from typical comets found within our Solar System.
Age and Origins of 3I/ATLAS
Research conducted by astronomers at the University of Oxford estimates that 3I/ATLAS may have formed in the Milky Way’s thick disk, a region populated by stars that emerged during the galaxy’s formative years, long before the birth of our Sun, which is about 4.6 billion years old. Using a statistical model of stellar age distribution, the team suggests that 3I/ATLAS could be between 8 billion and 14 billion years old, with a confidence level of 68%.
Supporting this finding, independent analysis from researchers at the University of Michigan indicates an age range of 3 billion to 11 billion years based on the object’s high galactic velocity. This approach involves comparing the motion of 3I/ATLAS to established age-velocity lines observed in stars. Collectively, this evidence suggests that 3I/ATLAS is likely the oldest comet-like object ever identified.
The original parent star of 3I/ATLAS remains undetectable, having drifted through the Milky Way for billions of years. Due to gravitational interactions with other stars and galactic structures, any specific path back to its birth system has been obscured. As a result, its “stellar birth certificate” has been effectively lost to time.
Cometary Characteristics and Scientific Consensus
3I/ATLAS exhibits typical cometary features, including a glowing coma of gas and dust formed as its icy materials heat up when exposed to sunlight. It displays a tail pushed away by solar radiation, along with a notable composition rich in carbon dioxide, water vapor, and other volatiles. Despite the intriguing characteristics, scientists affirm that there is no credible evidence suggesting artificial origins or propulsion systems.
While some speculative theories, including those proposed by astrophysicist Avi Loeb, have gained media traction, the astrophysics community largely dismisses these ideas as lacking in scientific foundation. The notion of 3I/ATLAS being an alien probe does not align with the available data.
The close approach of 3I/ATLAS to the Sun, anticipated around October 30, 2025, offers a valuable opportunity for observation. The object will reach its nearest point to Earth on December 19, 2025, at a distance of approximately 1.8 astronomical units, significantly closer than Mars. As it continues its journey out of the Solar System, its visibility will diminish, but the data collected during its flyby will be invaluable for future research.
Scientists are optimistic that the insights gained from studying 3I/ATLAS will enhance our understanding of planetary system formation and evolution across the universe. In a cosmos spanning billions of years and trillions of kilometers, this ancient traveler serves as a time capsule, preserving clues about the star nurseries and systems that once existed. Its path illustrates how even the smallest celestial bodies can convey profound narratives about existence in the universe.
