So each pair of $500k tickets buys the raw fuel for one BFR launch. If it takes 6 BFR launches to get one BFS to Mars, you need to sell 12 $500k tickets (or 24 $250k tickets) to pay for the fuel.

I don't think the limit is how fast you can get them there, but how fast you can build somewhere for them to live.How many cities on Earth, built from scratch, had 1M inhabitants in less than 50 years, less than 100 years etc in STABLE accommodation (i.e. not shanty towns). Not many, if at all.

Quote from: launchwatcher on 12/19/2017 10:55 amSo each pair of $500k tickets buys the raw fuel for one BFR launch. If it takes 6 BFR launches to get one BFS to Mars, you need to sell 12 $500k tickets (or 24 $250k tickets) to pay for the fuel.Propellant is completely in the noise, compared to BFS cost to Mars.

I see a delay for several synods before families emigrate. Wait to check out environmental affects on humans. Then the next gating factor would be the ability to construct large living spaces that would make families beyond the first few thousand really want to go. Elon said it would be fun. Need to make it so. Just takes a few more synods.

Like the fact the BFS passenger quantity can be increased in the spreadsheet. I don't think that a BFR/BFS architecture and design implemented in the teens will survive deep into the 2040s when really mass emigration of families beyond initial base(s) construction. SpaceX is the last company that would stop innovating. A 2 decade return on the base BFS design plus enhancements F9 to Block 5 style would be a nice return on the teens design. Maybe "Block 5" BFSs would be used late 40s and beyond as shuttle vehicles Mars surface to orbit unloading really massive MCTs Mars Colonial Transports carrying 500-1,000 colonists. These MCTs would never touch a planetary surface.

Propellant is completely in the noise, compared to BFS cost to Mars.If we assume that BFR cost is $100M, then just to keep pace with interest at 5% is $6M or so.If you start actually trying to pay off the investment in 10 years, it's more like $25M than the $6M of fuel.

How many cities on Earth, built from scratch, had 1M inhabitants in less than 50 years, less than 100 years etc in STABLE accommodation (i.e. not shanty towns). Not many, if at all.

I may be doing it wrong? But the formula for children feels weird to me; if I put 4 in cell D9 it looks like each couple has that many kids per window. So 4 in that cell means each woman is having a kid every 6 months window after window?Again, likely me doing it wrong, but I'm having fun playing with it. Thanks for putting it together!

It's interesting to consider that Alaska has a population of only 742k. The point being that even with a gold Rush and a payment to residents for oil drilling, "modern" man hasn't populated a easy real estate* with more than 3/4 million people in 150 years. It might be good to consider a lower bounds to keep the discussion grounded; Historically there have been 0 people on Mars.*(Easy compared to Mars)

Quote from: JamesH65 on 12/19/2017 02:13 pmI don't think the limit is how fast you can get them there, but how fast you can build somewhere for them to live.How many cities on Earth, built from scratch, had 1M inhabitants in less than 50 years, less than 100 years etc in STABLE accommodation (i.e. not shanty towns). Not many, if at all.https://en.m.wikipedia.org/wiki/Demographic_history_of_DetroitDetroit went from 285k in 1900 to over 1.5M in 1930 with stable accommodations. There are likely many others, I just had a notion that it applied to Detroit and confirmed it. Of course Detroit wasn’t built from scratch, just scaled by over a million in 30 years.https://en.m.wikipedia.org/wiki/Demographics_of_ChicagoChicago is a good fit going from almost nothing in 1840 to over 1 million in 1890. Whether it meets the stable criterion, not sure.

Looking at the topic slightly differently:What does it take to get to a million people on Mars?-A reason for them to be there.