; and (5) shall require at least one uncrewed and one crewed in-space test and demonstration prior to its use to carry astronauts to the surface of the Moon and a plan for testing of a Mars human lander in a suitable environment. (c) Exploration Space Suits The Administrator shall develop an exploration space suit to meet the requirements of the Moon to Mars Program. In developing an exploration space suit, the Administrator shall, to the greatest extent practicable, leverage prior and existing investments in advanced space suit technologies in order to maximize the benefits of such investments and technologies. The Administrator shall use the International Space Station for testing of exploration space suits. (d) Logistics Support To the maximum extent possible, logistics support to the Gateway to Mars and the lunar surface shall be provided by commercial services, provided that the availability of those services does not becoming the limiting critical path factor in NASA’s ability to complete its Gateway to Mars and Lunar Precursor initiatives as scheduled. The Administrator shall develop contingency plans for the delivery of the minimum set of needed logistics in the event commercial services are not available when needed. (e) International Collaboration (1) In general The Administrator shall lead and encourage to the maximum extent practicable international partner participation in the implementation of the elements of the Moon to Mars Program under overall NASA leadership. The Administrator shall encourage partnerships that enhance the program. (2) Congressional Authorization NASA shall seek Congressional authorization prior to finalizing any exploration architecture that depends on international or commercial partnerships for overall mission success. (f) Crewed Lunar Landing Missions In order to minimize the time required for the Lunar Precursor Initiative phase of the Moon to Mars Program, NASA shall plan for and implement measures to enable a crewed lunar landing mission rate of at least two per year