中国天问一号火星轨道器于2026年7月用高分辨率相机成功拍摄到星际彗星3I/ATLAS[1]。这次观测距离约3000万公里[1]，拍摄到的图像显示了彗星的尾部和昏迷[1]，证实该彗星含有水等易挥发物质[1]。
天问一号已在火星轨道运行四年八个月[1]，此次观测成为其在轨期间的重要科学成果。3I/ATLAS彗星直径约5.6公里[1]，以约58公里每秒的速度运行[1]，相对天问一号的速度约为86公里每秒[1]。该彗星于2025年5月7日被发现[1]。欧洲火星轨道器——火星快车号和火星微量气体轨道器——也在10月3日拍摄了这颗彗星[1]。
China's Tianwen-1 Mars orbiter successfully photographed the interstellar comet 3I/ATLAS in July 2026 using its high-resolution camera, capturing detailed images of the comet's tail and coma at a distance of approximately 30 million kilometers [1]. The observations provided evidence that the comet contains volatile substances including water [1]. This achievement marks a significant scientific milestone for Tianwen-1, which has been operating in Mars orbit for four years and eight months [1].
The comet, discovered on May 7, 2025, measures approximately 5.6 kilometers in diameter and travels at roughly 58 kilometers per second, reaching a relative velocity of about 86 kilometers per second with respect to Tianwen-1 [1]. Tianwen-1 was not alone in documenting this celestial visitor; European Mars orbiters, including Mars Express and the Trace Gas Orbiter, also captured images of 3I/ATLAS on October 3 [1]. The European Space Agency's Comet Interceptor mission is expected to complete its observations by 2029 [1].