Astronomers Discover 3I/ATLAS, Largest Interstellar Comet Yet Detected
Astronomers have discovered 3I/ATLAS, the third known interstellar comet to pass through our solar system. Detected by the ATLAS telescope in Chile, it’s racing inward at 150,000 mph and will swing closest to the Sun in October. Estimated to be 10–20 kilometers across, it is likely the largest interstellar object observed so far. Signs of cometary activity suggest it’s an icy relic from another star system. Early detection has given astronomers time to study its composition before it’s altered by solar heating—offering rare insight into planet formation beyond our own system.
NASA’s New Horizons Proves Deep-Space Navigation via Stellar Parallax
NASA’s New Horizons spacecraft accomplished a world-first by performing a deep-space stellar navigation test using stellar parallax. On April 23, 2020, while 438 million miles from Earth, it imaged nearby stars Proxima Centauri and Wolf 359. From the spacecraft’s distant viewpoint, the stars appeared slightly shifted compared to Earth-based observations, showcasing a clear demonstration of stellar parallax. By comparing these images with Earth data and a 3D star chart, scientists accurately determined New Horizons’ position within 4.1 million miles. This groundbreaking achievement proves that a spacecraft can navigate autonomously by observing stars using onboard cameras. The technique reduces reliance on Earth-based tracking systems and offers a viable navigation method for future missions to the outer solar system and beyond. NASA sees this as a vital step toward interstellar travel and self-guided deep-space exploration.