Core Points - The third interstellar visitor to the solar system, 3I/ATLAS, is accelerating towards the Sun, currently at a speed of approximately 63.1 kilometers per second and a distance of about 420 million kilometers from the Sun [8] - It is predicted that 3I/ATLAS will reach its perihelion around October 29, coming within about 200 million kilometers of the Sun, positioned between the orbits of Mars and Earth, with a speed of approximately 68 kilometers per second at that time [3][9] - The brightness of 3I/ATLAS has increased from a magnitude of 18 at discovery to approximately 16.3 currently, and it is expected to reach about 14.3 at perihelion [5][9] Group 1 - 3I/ATLAS was discovered in early July when it was about 670 million kilometers from the Sun, moving at a speed of approximately 61.3 kilometers per second [8] - After passing perihelion, 3I/ATLAS will quickly exit the solar system and is expected to reach beyond Neptune's orbit in less than three years [9] - The mass of 3I/ATLAS is negligible compared to planets or large asteroids, and it maintains a safe distance from known celestial bodies, posing no threat to Earth [9] Group 2 - 3I/ATLAS is classified as a comet due to its active nature, with a cold nucleus and cometary outgassing, and its nucleus is estimated to be no more than 5.6 kilometers in diameter [10] - The trajectory of 3I/ATLAS will take it through various constellations, including Serpens, Scorpius, Libra, and Virgo, with ground-based telescopes expected to capture observations until early October [10] - The scientific value of 3I/ATLAS is significant, providing a unique opportunity to study the composition of exo-objects, planetary formation processes, and ancient materials from the galaxy [10]
【新华社】第三位“星际访客”正加速靠近太阳
Xin Hua She·2025-08-22 00:38