3I/ATLAS, the third confirmed interstellar object detected in our solar system, was discovered on July 1, 2025, by the ATLAS (Asteroid Terrestrial-impact Last Alert System) survey. Unlike solar system comets, this visitor hails from the vast interstellar void, tracing a hyperbolic orbit that ensures it will swing by the Sun and depart forever, never to return. hurtling through space at nearly 60 km/s (about 135,000 mph) relative to the Sun, it ranks among the swiftest natural objects humanity has ever observed. For now, 3I/ATLAS remains a faint speck, visible only through professional telescopes, but its activity is ramping up as it nears the inner solar system. Mysteries abound regarding its physical traits: debates persist over its precise dimensions, luminosity, and makeup. Recent estimates peg the nucleus at 1-2 kilometers wide, based on Hubble Space Telescope data from August 2025, while a surrounding coma of sublimating ices blurs its outline. Recent observations have unveiled exciting new details about 3I/ATLAS's behavior. In late August 2025, the Gemini South telescope captured images revealing a developing tail of dust and gas, affirming its cometary activity as it warms in the Sun's glow. By September 7, 2025, astrophotographers noted a striking color evolutionâfrom reddish tones to vibrant green-blue shadesâlikely driven by surging emissions of cyanide (CN) gas, as highlighted by astrophysicist Avi Loeb. Early September brought another revelation: NASA's SPHEREx mission identified a hazy "carbon dioxide fog" encasing the comet, signaling vigorous sublimation of CO2 ices as it closes in on the Sun. Adding to the intrigue, a study released around September 10, 2025, reported unprecedented negative polarization in its reflected light, a trait unseen in any solar system body, hinting at exotic surface materials or structures that warrant further scrutiny.