AI 中文总结
该研究通过多仪器观测表征了适合JUICE飞掠的千米级木卫卡里科雷，降低了其轨道不确定性，确定了形状、尺寸等参数，为JUICE飞掠提供了可行条件。
AI 中文摘要
木星的不规则卫星被认为是早期太阳系星子的遗迹，然而它们体积小、距离地球远且角位置靠近木星，难以通过遥感进行表征。本文报告了对千米级卫星卡里科雷（Kallichore）的多仪器观测结果，它是木星唯一适合欧洲空间局（ESA）木星冰卫星探测器（JUICE）近距离飞掠的不规则卫星，此前其天体测量和物理性质仍知之甚少。我们利用哈勃空间望远镜的测光和天体测量数据，随后开展了地面多站点恒星掩星观测活动，以及使用10.4米加那利大型望远镜的天体测量和测光观测。我们将卡里科雷的轨道不确定性降低了约80%，并确定了其形状：一个细长天体，最小半长轴比a/b为1.53±0.10，面积等效直径为3.8（+2.3/-0.3）千米，表面较暗，几何反照率为3.7%（+0.7/-2.2），未探测到近距伴星。这些新的约束条件为JUICE在2031年抵达木星系统后开展飞行动作提供了可行路径。
英文摘要
Jupiter's irregular satellites are thought to be relics of early Solar System planetesimals. However, their small sizes, large distances from Earth and close angular proximity to Jupiter make them difficult to characterize remotely. Here we report multi-instrument observations of kilometre-sized Kallichore, the only irregular moon of Jupiter amenable to a close flyby by ESA's Jupiter Icy Moons Explorer (JUICE), whose astrometric and physical properties were still poorly constrained. We used Hubble photometry and astrometry, followed by a ground-based, multi-site stellar occultation campaign and astrometric and photometric observations with the 10.4-m Gran Telescopio Canarias. We reduced Kallichore's orbital uncertainty by up to approximately 80% and determined its shape: an elongated object with a minimum semi-axis ratio of a/b = 1.53 +/- 0.10, an area-equivalent diameter of 3.8 (+2.3/-0.3) km and a dark surface with a geometric albedo of 3.7% (+0.7/-2.2). No close companions were detected. These new constraints provide a viable pathway towards a JUICE flyby once the spacecraft arrives in the Jupiter system in 2031.
CommentsPublished in Nature Astronomy on 24 July 2026
Journal refNature Astronomy (2026)
DOI：10.1038/s41550-026-02929-z
