Re: Some points about passengers and P2P
I don't think every kilo of water that you drink on your trip to mars is going to be a brand new bottle of Fiji water. It's going to be urine recyc. So maybe 3.5kg of emergency water per person (total not per day) and perhaps a 20kg machine with a 100l holding tank, plus a standby plus some spares and tools. That brings the water down from 63 tonnes to ~1/2 tonne.