Jupiter’s moon Europa may have the potential to harbor life. The spacecraft will use multiple flybys of the moon to investigate the habitability of this ocean world.

Europa Clipper, NASA’s upcoming flagship mission to the outer solar system, has passed a significant milestone, completing its Critical Design Review. During the review, experts examined the detailed design of the spacecraft to ensure that it is ready to complete construction. The mission is now able to complete hardware fabrication and testing, and move toward the assembly and testing of the spacecraft and its payload of sophisticated science instruments.

With an internal global ocean twice the size of Earth’s oceans combined, Jupiter’s moon Europa carries the potential for conditions suitable for life. But the frigid temperatures and the nonstop pummeling of the surface from Jupiter’s radiation make it a tricky target to explore: Mission engineers and scientists must design a spacecraft hardy enough to withstand the radiation yet sensitive enough to gather the science needed to investigate Europa’s environment.