“星际访客”新图像公布，天文学家：可能比太阳系更古老

Core Viewpoint - Astronomers have observed a new interstellar object, 3I/ATLAS, which is the third such "interstellar visitor" discovered to date, traveling through the solar system at high speed [1][5]. Group 1: Discovery and Characteristics - The ATLAS telescope, funded by NASA, first reported the discovery of 3I/ATLAS on July 1, 2023, initially marking it as object A11pl3Z before officially naming it [3]. - The calculated orbital eccentricity of 3I/ATLAS is 6.2, indicating it originates from outside the solar system, with a speed exceeding 60 kilometers per second as it traverses the solar system [3]. - Current observations suggest that 3I/ATLAS exhibits characteristics typical of comets, although its exact size remains undetermined, with estimates suggesting a diameter of around 20 kilometers [3]. Group 2: Scientific Implications - A research team led by Matthew Hopkins from Oxford University posits that 3I/ATLAS may be an older celestial body than those in the solar system, potentially originating from the galactic thick disk, which contains older stars [4]. - The likelihood that 3I/ATLAS is older than the solar system is estimated at two-thirds, with the possibility that it has been drifting in interstellar space for a significant period [4]. Group 3: Future Observations - As of now, 3I/ATLAS is located approximately 465 million kilometers from Earth and 600 million kilometers from the Sun, expected to reach its closest point to the Sun at about 210 million kilometers around October 30, 2023 [5]. - The interstellar object is projected to come closest to Earth in December 2023, at a distance of approximately 270 million kilometers, posing no threat to Earth [5].