How can a sustained human presence on Mars be maintained when, due to orbital mechanics, resupply rockets are only in the launch window every 26 months?
The distance between Earth and Mars constantly fluctuates (from 55.76 to 401 million km) as both planets orbit the Sun at different speeds. For this reason, space missions utilize a narrow launch window to minimize fuel consumption and travel time.
After the live stream I lay awake for a long time! I had to think about whether my guess of 10 refuelings was correct! Unfortunately I didn't come to any conclusion!