The Comet Interceptor mission

Kurzfassung

All comets that have been encountered by spacecraft so far are short-period comets: objects that have approached the Sun many times, and have thus undergone changes on their surfaces, erasing their original appearance and make-up. A true, pristine comet has yet to be encountered and explored. Such objects are difficult to target because they can only be discovered when approaching the Sun for the first time, leaving little time to plan and launch a mission to them. Advances in technology are now making such a mission possible. A new generation of powerful survey telescopes, including the upcoming Large Synoptic Survey Telescope, LSST, are discovering comets far enough away as they approach the Sun that they can be targeted by space missions. Comet Interceptor is an European Space Agency (ESA) mission, developed in cooperation with the Japan Aerospace Exploration Agency (JAXA) to address this challenge of exploring a pristine comet. It aims to characterise through a close flyby a long period comet, preferably dynamically new, or an interstellar object. The main spacecraft will be accompanied in its encounter with the target comet’s nucleus by two small probes, one provided by Europe, andthe other one by Japan. The mission was adopted in 2022 and is scheduled for launch in 2029. The mission will wait at the Lagrange point L2 until a suitable target is found, then depart from its waiting position and intercept the comet. The international Science Working Team (SWT) is supported in specific scientific and science operation areas by Working Groups (WGs). These are the Target Identification WG and Comet Environment WG. The latter comprises three sub-WGs, covering the Nucleus, Near-Environment, and Far-Environment. Here, we provide a brief overview of the mission, and present and describe the aims and activities of the WGs. The search is already underway for potential comets to encounter, and preparations are being made for the scientific exploitation of the data from the mission’s three spacecraft.