Preface: On December 31, 2025, interstellar comet 3I/ATLAS is well past its closest approach to Earth (December 19, 2025) and is already heading back out of the solar system on a hyperbolic trajectory, still visible with telescopes in the Northern Hemisphere as it moves through the constellation Leo, offering a unique opportunity for astronomers to study this visitor from another star system before it disappears forever!
Background: An interstellar object discovered in July that is travelling at high speed and unlike anything seen before, touches on a fascinating area of modern astronomy, particularly the relatively new field of identifying celestial visitors from beyond our solar system. 3I/ATLAS carrying chemical clues that suggest its parent system was rich in carbon dioxide and possibly very old, originating from the Milky Way’s thick disk. While some of its anomalies sparked speculative discussions, the scientific consensus firmly identifies it as a fascinating, albeit unusual, natural comet. Its study is a goldmine for understanding the vast diversity of planetary formation processes across the galaxy. Harvard astrophysicist Avi Loeb has kept the interstellar object 3I/ATLAS at a Rank 4 on his Classification Scale (0-10, 10 being alien tech) because, despite numerous anomalies like an unusual anti-tail and unexplained mass loss, the data isn’t conclusive enough for a higher rating, though he believes its features suggest potential technological origin, keeping it significantly above natural comets like ‘Oumuamua, while awaiting more data from upcoming observations.
Mainstream perspective: The scientific definition based on causality is the cornerstone of scientific inquiry and the foundation of human understanding of the world. However, causality in science is not a simple definition. We may know that the 3I/ATLAS interstellar object does not have conclusive evidence that it is an extraterrestrial visitor. However, extraterrestrial life originates from an unknown universe. Interstellar objects also originate from this unknown universe. From a scientific perspective, there is some kind of connection between them.
Today is the last day of 2025. Perhaps it’s time to say goodbye to 2025.
Andrea Bocelli, Sarah Brightman – Time To Say Goodbye –