NASA never called it a one-way mission to Mars.
They called it a colonization mission.
But the crew knew that once they were on their way, they’d never come back.
NASA launched a series of cargo pods at Mars before launching the colonists.
The plan was to build the colony with all those materials.
Instead, an asteroid took out the lead cargo pod, and the debris knocked the others off course.
The colonists were carrying some supplies, but not enough.
And even if emergency supplies could be launched, the launch window had passed.
NASA finally called the doomed mission “one-way.”