In article ,
Rand Simberg wrote:
Think how much harder it is to build a car that goes 120 mph than a
bicycle that goes 12 mph. Now think how much harder it is build a jet
that goes 1,200 mph than a car. Now take it one step further and you've
got the difficulty of manned spaceflight.

Funny thing is, it doesn't cost much more to to fly across country
than it does to drive, especially when one takes the full costs
(depreciation, etc.) into account.

But that's not the cost per pound, that's the cost per pound *per mile*.
Assuming 120 orbits, the space shuttle travels 3 million miles, which
at $10,000 per pound is 1/3 of a cent per pound per mile. That's only
3 to 10 times as high as a plane ticket, not two orders of magnitude.

Heck, an LEO satellite might have 50,000 useful orbits, while Saturn is a
billion miles away. Space is already the cheapest form of transportation
counting your way. :-)

--
/\ Greg Kuperberg (UC Davis)
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