We describe the AMBITION project, a mission to return the first-ever cryogenically-stored sample of a cometary nucleus, that has been proposed for the ESA Science Programme Voyage 2050. Comets are the leftover building blocks of giant planet cores and other planetary bodies, and fingerprints of Solar System’s formation processes. We summarise some of the most important questions still open in cometary science and Solar System formation after the successful Rosetta mission. We show that many of these scientific questions require sample analysis using techniques that are only possible in laboratories on Earth. We summarize measurements, instrumentation and mission scenarios that can address these questions. We emphasize the need for returning a sample collected at depth or, still more challenging, at cryogenic temperatures while preserving the stratigraphy of the comet nucleus surface layers. We provide requirements for the next generation of landers, for cryogenic sample acquisition and storage during the return to Earth. Rendezvous missions to the main belt comets and Centaurs, expanding our knowledge by exploring new classes of comets, are also discussed. The AMBITION project is discussed in the international context of comet and asteroid space exploration.

我们描述了野心项目，这是一项返回有史以来第一个低温储存的彗星核样本的任务，已为欧空局科学计划航程 2050 提出。彗星是巨大行星核心和其他行星体的剩余构件，也是太阳的指纹系统的形成过程。我们总结了在成功的罗塞塔任务之后彗星科学和太阳系形成中仍然悬而未决的一些最重要的问题。我们表明，许多这些科学问题需要使用只有在地球上的实验室才能实现的技术进行样本分析。我们总结了可以解决这些问题的测量、仪器和任务场景。我们强调需要返回在深度收集的样本，或者更具挑战性的是，在低温下，同时保留彗核表面层的地层。我们为下一代着陆器提供要求，在返回地球期间进行低温样品采集和存储。还讨论了主带彗星和半人马座的会合任务，通过探索新的彗星类别来扩展我们的知识。这AMBITION项目是在彗星和小行星空间探索的国际背景下讨论的。