天问一号成功观测到星际天体阿特拉斯

Core Viewpoint - The successful observation of the interstellar object ATLAS by the Tianwen-1 orbiter represents a significant expansion of its mission capabilities, providing valuable data for future asteroid exploration by Tianwen-2 [2][8]. Group 1: Observation Details - The Tianwen-1 orbiter utilized a high-resolution camera to observe the interstellar object ATLAS from approximately 30 million kilometers away, marking one of the closest observations of this celestial body [2][8]. - The high-resolution camera captured images that clearly displayed the comet-like features of ATLAS, which has a diameter of several thousand kilometers [4]. - A series of images taken over 30 seconds were compiled into an animation to illustrate the motion trajectory of ATLAS, aiding in further research [4]. Group 2: Scientific Significance - ATLAS, discovered on July 1, 2025, by a telescope in Chile, is the third known interstellar object to visit the solar system, traveling on a hyperbolic trajectory [9]. - The object is estimated to be between 3 billion and 11 billion years old, potentially older than the solar system itself, making it a rare sample for studying the composition and evolution of exoplanets and early stellar history [9]. - The Tianwen-1 team began preparations for observing ATLAS in early September, facing challenges due to the object's great distance, high speed (approximately 58 km/s), and small size (nucleus diameter of about 5.6 km) [9]. Group 3: Technical Challenges and Solutions - The high-resolution camera on Tianwen-1 was originally designed for capturing bright Martian surfaces, making this the first attempt to photograph such a distant and faint target, which is 10,000 to 100,000 times dimmer than Martian surfaces [13]. - The Tianwen-1 team conducted extensive simulations and feasibility assessments to adapt the camera's capabilities for this challenging observation, ultimately achieving successful imaging of ATLAS [13]. - The mission has been operational since February 2021, maintaining a stable status for over 4 years and 8 months [14].