Economics of spaceflight

[sojourner]

Cities are not really an issue when it comes to efficient land use. If everyone lived in population densities like Tokyo, Hong Kong or New York we'd have plenty of farmland. It's the damn suburbs that are a waste of space and don't get me started on golf courses. Ghad! the amount of land wasted (among other resources) on a single sport where old men ride around in little carts whacking little balls. It pisses me off.

[Khrissetti]

RPayne was hypothesising about a future world where land was so scarce that colonising another world is being considered. In that sort of world (approaching ecumenopolis state) we'd more likely consider my suggestions before heading for the barren worlds of Mars et al.

As for cities and land use, you have to consider more than the physical buildings and tarmac, they require much more land for water, food, energy, etc. While a city centre is more efficient than a suburb, we can still improve them greatly. If you've ever been to any of the super-big cities like Beijing you'll know how we need to improve efficiency and air quality.

Also, as a city centre dweller (in an apartment with a great view) which couldn't be much closer to the zero-point if I tried, I salute and approve of this anti-suburb chauvinism!

[Nuke]

We'll switch to a primarily vegetarian diet before we move to Mars for more food. Meat consumes an obscene amount of land to grow, if overcrowding gets that bad, meat will be too expensive to produce. Trust me, it isn't such a bleak prospect!

Further, there is massive untapped room for food to grow on rooftops and basket crops, hopefully we'll start to take more advantage of rainwater and greywater harvesting in the next few years in our cities. Current city designs are massively unsustainable, but the potential is there. The Vertical Farm project is just one idea to help with this project: http://www.verticalfarm.com/

A change in diet, greater sustainability of our cities and the 'greening' of concrete spaces are all tactics we'll use before we start to think about sending people to Mars (And they're tactics we should really be doing now.)

http://www.news.cornell.edu/stories/2007/10/diet-little-meat-more-efficient-many-vegetarian-diets

speak for yourself, im resorting to cannibalism.