Challenges of Mars Mission Phase Transitions on Spacecraft Environmental Control and Life Support Systems

Deep space human exploration mission concepts presented at the NASA Advisory Council (NAC) Human Exploration and Operations (HEO) Committee meetings NASA exploration concept include a multi-vehicle architecture, including a Deep Space Gateway(DSG) that would stay in a cis-lunar orbit, and a Deep Space Transport (DST) vehicle that would transport crew to exploration destinations, including Mars. The mission timeline calls for these vehicles to undergo alternating uncrewed and crewed periods over the course of the mission. Previous works have assessed the implications of long-term uncrewed periods to the spacecraft Environmental Control and Life Support Systems (ECLSS) design and operation. The interest in this work is in examining the transition between these modes within the framework of the Mars mission timeline for nominal and off-nominal concepts of operation. These transitions must be well planned with a detail sequence of events in order to ensure the systems are placed in states that will adequately support the target mission phase as well as future transitions. We will look at the steps that must be considered and their sequencing to develop an approach that supports and enables a successful human mission to Mars.