What key requirement for the Artemis missions adds substantial complexity to the Starship system being tested?

Answer

The required ability to conduct multiple in-orbit refueling operations autonomously

A major factor adding significant complexity to the required reliability of the Starship HLS variant is the necessity to autonomously transfer thousands of gallons of super-cold propellants during multiple refueling operations in orbit.

What key requirement for the Artemis missions adds substantial complexity to the Starship system being tested?
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