I don’t know the numbers for Starship specifically, but this is a matter of how much fuel you have available to burn, and six months has long been considered re

I don’t know the numbers for Starship specifically, but this is a matter of how much fuel you have available to burn, and six months has long been considered reasonable. For a free-return trajectory (end up back at Earth if you’re not willing or able to conduct a Mars entry burn), the minimum-energy trajectory takes 250 days (8.3 months) and requires 3.34 km/s delta-V. Getting it down to 180 days takes 5.08 km/s, so about 50% more delta-V (and fuel). Getting there faster is possible but starts to run into diminishing returns, especially because it makes aerobraking at Mars more and more difficult, requiring even more fuel for slowing down on arrival. These numbers are from Robert Zubrin’s “The Case for Mars” (1996) which assumed a six-month transit time would be the norm for human missions. Fantasies of moving to Mars to escape climate change are stupid—even under the best terraforming projections and the worst climate change projections, Earth will be several orders of magnitude more habitable for centuries at least. But the scientific return from a once-warm-and-wet world is more than enough reason to go. Someone like NASA’s Jessica Watkins, who did her dissertation on Martian geology at Caltech, certainly would not be counting down the sols.