This crucially depends on a 70ton (LEO) launcher and it&#x27;s no guarantee SLS will get off the ground. It&#x27;s also uncertain if private actors manage to put together reliable heavy launchers, even by 2020-2025.<p>This is also only a lander and not a rover, but any lander will be valuable, mobile or not. Obviously, Europa has only 35% of Mars&#x27; gravity, so a wheeled rover may not even work in those conditions, including the rugged and difficult surface to traverse.