Enlarge / For now, Starship's first mission will be to the Moon. (credit: Elon Musk/Twitter) For months in south Texas, SpaceX employees have been assembling a test version of the upper stage for its next-generation launch system. This prototype "Starship" is far from space-worthy, but it will allow the company to test the vehicle's ability to "hop" from the spaceport and then land propulsively back on the ground. On Friday, the company sent a notice to nearby residents saying it planned to conduct testing of the vehicle as soon as the week of March 18, and that it would be closing the main roadway of Highway 4 to non-residents during the tests.