In article ,
John Savard wrote:
...What's lacking are companies that would be willing to do
it as expensively as the use of a CEV would require.

...are you claiming that there are ways, absent the development of
far-future technologies such as a space elevator (or non-Newtonian
propulsion!), to send personnel to the moon at prices that would be
rational for even a *few* private companies to take advantage of?

There's no fundamental reason why not. The only absolutely inescapable
cost of doing so is fuel... and fuel is cheap. The fundamental cost of
putting mass into orbit with LOX/kerosene is under $1.50/kg. Of course,
most of that mass is vehicle; it'll be up around maybe $8/kg for payload.
There will be some other operating costs, not large by comparison because
rockets are so fuel-intensive. Call it $10/kg to LEO.

Handily, the delta-V for TLI, landing, and return is about the same as for
reaching LEO. So similar mass ratios apply, and we get a cost of around
$1000/kg for payload to the lunar surface and return. That could be
reduced significantly with refueling on the lunar surface, and perhaps
further with lunar LOX exported to LEO, but I'll disregard those options.
Figuring person plus spacesuit plus baggage plus odds and ends at 200kg, a
return ticket is $200,000. Which is a lot for an individual and nothing
much for a company.

The trick is getting the overhead costs down to a small fraction of fuel
costs. We are nowhere near achieving that; currently the overhead costs
are utterly dominant and fuel costs are insignificant. It would take
fully-reusable highly-developed hardware, greatly streamlined operations,
and a high flight rate. There's not the slightest chance that NASA could
do that. But there is nothing impossible about it.

Of course, looking at prices in my local department store... if it
weren't for the effects of the balance of payments deficit, perhaps the
U.S. could just buy Shenzou rockets from China!

Not that helpful, not on this scale. Cheap hardware, but it's still
expendable... and it uses quite costly fuels, much more expensive than
LOX/kerosene.

(By the way, Shenzhou is the spacecraft -- the rockets are Long March.)
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