Here we describe the novel, multi-point Comet Interceptor mission. It is dedicated to the exploration of a little-processed long-period comet, possibly entering the inner Solar System for the first time, or to encounter an interstellar object originating at another star. The objectives of the mission are to address the following questions: What are the surface composition, shape, morphology, and structure of the target object? What is the composition of the gas and dust in the coma, its connection to the nucleus, and the nature of its interaction with the solar wind? The mission was proposed to the European Space Agency in 2018, and formally adopted by the agency in June 2022, for launch in 2029 together with the Ariel mission. Comet Interceptor will take advantage of the opportunity presented by ESA’s F-Class call for fast, flexible, low-cost missions to which it was proposed. The call required a launch to a halo orbit around the Sun-Earth L2 point. The mission can take advantage of this placement to wait for the discovery of a suitable comet reachable with its minimum \(\varDelta \)V capability of \(600\text{ ms}^{-1}\). Comet Interceptor will be unique in encountering and studying, at a nominal closest approach distance of 1000 km, a comet that represents a near-pristine sample of material from the formation of the Solar System. It will also add a capability that no previous cometary mission has had, which is to deploy two sub-probes – B1, provided by the Japanese space agency, JAXA, and B2 – that will follow different trajectories through the coma. While the main probe passes at a nominal 1000 km distance, probes B1 and B2 will follow different chords through the coma at distances of 850 km and 400 km, respectively. The result will be unique, simultaneous, spatially resolved information of the 3-dimensional properties of the target comet and its interaction with the space environment. We present the mission’s science background leading to these objectives, as well as an overview of the scientific instruments, mission design, and schedule.

在这里，我们描述了新颖的多点彗星拦截器任务。它致力于探索一颗未经处理的长周期彗星，可能是第一次进入内太阳系，或者遇到源自另一颗恒星的星际物体。该任务的目标是解决以下问题：目标物体的表面成分、形状、形态和结构是什么？彗发中的气体和尘埃的成分是什么，它与原子核的联系，以及它与太阳风相互作用的性质是什么？该任务于2018年向欧洲航天局提出，并于2022年6月被该机构正式通过，将于2029年与Ariel任务一起发射。彗星拦截器将利用欧空局 F 级呼吁所提供的机会，执行快速、灵活、低成本的任务。该呼叫要求发射到围绕日地 L2 点的光环轨道。该任务可以利用这个位置来等待发现一颗合适的彗星，其最小\(\varDelta \) V 能力为\(600\text{ ms}^{-1}\) 。彗星拦截器将在名义上最近距离为 1000 公里的地方遭遇和研究一颗彗星，该彗星代表了太阳系形成过程中近乎原始的物质样本。它还将增加一项以前的彗星任务所没有的能力，即部署两个子探测器——由日本航天局、JAXA提供的B1和B2——它们将在昏迷中遵循不同的轨迹。主探测器的标称距离为 1000 公里，而探测器 B1 和 B2 将分别在 850 公里和 400 公里的距离处沿着不同的弦线穿过慧发区。 结果将是关于目标彗星的 3 维特性及其与空间环境相互作用的独特、同步、空间解析信息。我们介绍了实现这些目标的任务科学背景，以及科学仪器、任务设计和时间表的概述。