Addressing the Habitability of Europa with the Europa Clipper Mission
Abstract
The ice-covered world Europa, one of the four large Galilean satellites, may be a habitable world. Europa is about the same size as Earth's Moon and is mostly rock, with an outer ice-rich shell that is quite dynamic. Its young, bright, icy landscape is crisscrossed by a network of cracks and ridges, interrupted by smooth bands, disrupted chaotic terrain, and exhibits few large craters. Several lines of scientific evidence, which include observations of gravity and induced magnetic fields as well as results from thermal modeling of the moon's interior, point to the conclusion that Europa likely has a global ocean of water under the ice, maintained in liquid form by tidal flexing and heating as the moon moves in its eccentric orbit about Jupiter. The orbital eccentricity is maintained by gravitational resonances with the other Galilean moons and is likely long-lived. While the presence of the ocean is compelling, it is unknown whether Europa is for certain habitable. Thus, investigation of Europa is a top priority for planetary exploration. The science goal of NASA's Europa Clipper mission is: Explore Europa to investigate its habitability. The mission's three objectives are focused on Europa's ice shell and ocean, composition, and geology. To achieve the mission's science goal and objectives, the spacecraft will conduct more than 40 flybys of Europa with closest approach altitudes in the range of 25-100 km, with a capable suite of nine remote sensing and in situ instruments plus gravity science. During the time period near closest approach, the remote sensing instruments are in a nadir-looking orientation, the fields of view of the particle sensors encompass the Keplerian ram direction, and supplemental antennas enable gravity science. In this configuration, the entire payload can collect data simultaneously during the flybys. The anticipated observations will facilitate the search for subsurface water, chemistry compatible with habitability, and active geological processes. In studying Europa in depth, the Europa Clipper mission, currently in Phase B, will enable a leap in scientific understanding of ocean worlds and their potential habitability.
- Publication:
-
42nd COSPAR Scientific Assembly
- Pub Date:
- July 2018
- Bibcode:
- 2018cosp...42E1817K