July 1, 2025: NASA-funded ATLAS telescope in Chile detected the third known interstellar object passing through our solar system. 3I/ATLAS is the most scientifically significant interstellar visitor yet documented. Key facts from NASA, ESA, and Space.com’s comprehensive coverage: (1) AGE: July 2025 studies estimated 3I/ATLAS is between 7.6 and 14 billion years old — potentially older than our Solar System (4.6 billion years). Its parent star system may no longer exist. (2) SPEED: 58 km/s relative to the Sun — highest hyperbolic excess velocity of any known interstellar object. 130,000+ mph at discovery, accelerating to 153,000 mph at perihelion (October 29, 2025). (3) TRAJECTORY: Orbital eccentricity of 6.141 — essentially a straight-line path through the solar system, originating from the direction of Sagittarius near the Galactic Center. (4) SIZE: Hubble estimated nucleus diameter between 440 meters and 5.6 km — potentially largest interstellar object ever seen. (5) NON-GRAVITATIONAL ACCELERATION: Stronger than predicted from outgassing models — debated. Avi Loeb (Harvard) publicly speculated on ~40% probability of alien spacecraft origin. Mainstream astronomy consensus: confirmed as a natural comet. Space.com headline: “Interstellar comet 3I/ATLAS isn’t an alien spacecraft, astronomers confirm. ‘In the end, there were no surprises.'” (6) ESA JUICE CRITICAL: ESA’s Jupiter Icy Moons Explorer had the best observational view of 3I/ATLAS in its active state in November 2025 — but data transmission was limited because the spacecraft was using its high-gain antenna as a heat shield. The full JUICE data only arrived on Earth in February 2026. Instrument teams were still analyzing it as of April 2026. The final verdict on 3I/ATLAS’s composition and non-gravitational behavior has NOT yet been delivered. (7) ESA’s April 2026 update: emitting 70 Olympic swimming pools of water vapor per day, primarily toward the sun.