The cryo-penetrator: An approach to exploration of icy bodies in the solar system

Abstract

The nuclei of comets and the small icy moons of the outer planets are thought to be the most primitive objects in the solar system. Because of their pristine nature, in-situ measurements of composition, temperature, and mechanical properties will be a powerful tool in realization of one of NASA's major objectives: determination of the Solar System's origins and evolution.Cryo penetrators are a new class of penetrator vehicle investigated intensively since 1985 for NASA's Comet Rendezvous/Asteroid Flyby (CRAF) mission. They are specifically optimized for penetration and operation in icy bodies at temperatures below 150 degrees K. The CRAF studies were directed at investigation of comet nuclei, but the same design should be applicable to the icy moons of the outer planets and, with appropriate delivery systems, (similar to those envisioned for NASA's MESUR mission) to the Martian polar caps.This paper describes the design of a cryopenetrator based on the CRAF Configuration and designed for in-situ measurements of a comet nucleus as part of the Comet Nucleus Penetrator (CNP) Discovery mission. The ROSETTA nucleus rendezvous mission recently selected by ESA is another potential cryo penetrator application.