神秘“星际访客”，离地球近了！

Core Viewpoint - The article discusses the upcoming close approach of the interstellar object ATLAS (3I/ATLAS) on December 19, 2025, highlighting its significance for astronomical observation and research into the early formation of other planetary systems [1][4]. Group 1: Discovery and Characteristics - ATLAS was discovered on July 1, 2025, by a survey telescope in Chile and was initially classified as a long-period comet before being confirmed as an interstellar object with a hyperbolic orbit [1][3]. - It is the third interstellar object identified by humanity, all of which are classified as interstellar comets with open hyperbolic orbits, indicating they will not return after passing through the solar system [3][4]. Group 2: Observational Opportunities - ATLAS reached its perihelion on October 29, 2025, becoming brighter but was not optimally positioned for observation. It will reach its closest point to Earth on December 19, 2025, located near the zodiac in the constellation Leo [4]. - At its closest approach, ATLAS will have a brightness below magnitude 12, making it invisible to the naked eye and requiring professional telescopes for observation [4]. Group 3: Scientific Significance - Observing ATLAS is scientifically significant as it carries materials from another star system's early formation, which could provide insights into the "cradles" of other planets in the Milky Way [5].