Before revision: Particular targets are Europa, due to its potential for life, and Callisto, due to its relatively low radiation dose.Artemis Society International official website In 2003, NASA proposed a program called Human Outer Planets Exploration (HOPE) that involved sending astronauts to explore the Galilean moons.
After revision: In 2003, NASA proposed a program called Human Outer Planets Exploration (HOPE) that involved sending astronauts to explore the Galilean moons.