Can't wait to hear who booked this trip! Definitely one of the coolest ways to spend a lot of superfluous money :)
At least, I expect many will spin it that way.
The Shuttle and the new Space Launch System will use hydrogen/LOX, which exhausts basically water vapor.
The expensive, exotic, high-specific-impulse, but low-density and dangerous option is liquid hydrogen + liquid oxygen (hydrolox), which does indeed create water vapor as exhaust. This particular rocket, however, uses RP-1 (similar to jet fuel - just highly refined kerosene) + liquid oxygen - still burning hydrocarbons, still releasing CO2, but favored because it's cheap, dense, safe, and doesn't need cryogenic cooling.
For comparison, the ITS (and many other Mars mission concepts) use liquid methane + liquid oxygen (methalox), which also outputs CO2, needs cryogenic cooling and is not as safe or dense as RP-1/LOX, but is still safer and denser than hydrogen, doesn't need to be kept quite as cold, and is easy to synthesize on-site on another planet.
https://en.m.wikipedia.org/wiki/Kerosene The combustion reaction can be approximated as follows, with the molecular formula C12H26 (dodecane):
2 C12H26(l) + 37 O2(g) → 24 CO2(g) + 26 H2O(g); ∆H˚ = -7513 kJ
The atomic makeup of RP-1 is about CH1.97[1], so at stoichiometric ratio[2] that would yield 71.3% CO2 and 28.7% H2O by mass.
[1] http://www.qrg.northwestern.edu/projects/vss/docs/propulsion...
[2] in reality Falcon 9 burns fuel-rich
[1] http://www.grida.no/publications/other/ipcc_sr/?src=/climate... (kind of old, but I think the more recent IPCC reports are in a similar vein)
[2] https://eos.org/research-spotlights/the-forgotten-water-vapo...
This is all quite separate from the moral issue, to which I have nothing to add.
Energy usage is not the only consideration, and it certainly does matter what it exhausts. Exhausting an inert gas is definitely preferable to a greenhouse gas, which would be preferable to exhausting anthrax, etc.
The composition of the exhaust is going to affect the positivity of the public reaction to a billionaire burning it into public air space for leisure.
You may have a point regarding the public perception; don't really care to weigh in.
Uhh, what moral issue, exactly?
(1) It's much easier to orbit the moon than to land on it.
(2) Both the US and the USSR had the capability to send many people on orbital flights around the moon.
(3) With both the US and USSR orbiting the moon, the space race wouldn't have ended (because both had the same capability and neither had put a flag on the surface).
(4) Once both countries are orbiting the moon for a few years, at some point in the 1970s one or the other would have made a landing.
(5) Both great powers would be competing incrementally in the same space, but at the same time it's not a situation which could have plausibly lead to a war, so it would have been safe for humanity.
2) All the nations have a capability to stay on Earth
…
(plus or minus)
(Interestingly, the average cost of a 10 hr 747 flight is about $40k [about $14k for fuel, which is about 33% of costs], compared to $90m [estimated] for a Falcon Heavy launch. So one order of magnitude more fuel, but almost 4 orders of magnitude more price.)
[1] https://www.reference.com/vehicles/much-747-weigh-8b0c48a1d8... [2] https://en.wikipedia.org/wiki/Boeing_747-8 [3] https://en.wikipedia.org/wiki/Falcon_Heavy [4] https://www.quora.com/How-much-fuel-does-a-Boeing-747-or-777... [5] https://www.quora.com/How-much-of-the-cost-of-an-airline-tic...
However, not all rocket fuel/propellant is carbon based, in fact, most aren't.
However, there's also a lot of interest in using biofuels for aviation, so you may see that in the mid-term future we're using carbon-based fuels but they're largely carbon-neutral.
How? I'm not saying you're wrong, but gut instinct is that automobiles are more useful to humans. I'd like to hear your thought process.
clock_tower did so here, very excellently: https://news.ycombinator.com/item?id=13749603
(As for the other expenditures proposed above: real AOC Champagne supports the vineyards and traditional practices of the Champagne province of France; caviar... supports sturgeon fishermen? But consuming both together is just conspicuous consumption -- Champagne is a dessert wine. :) )
http://bart.volgers.eu/wp-content/uploads/2014/01/Dilbert-El...
Automobiles, while useful, are mostly a solved technology (unless you're buying Tesla or some other prototype, pushing-the-envelope model). Buying another one - or for that matter, making another typical automobile - has negligible marginal impact on advancement of technology. Taking humans to the Moon again - first time in 45 years - will have a huge impact both on our technological capacity as a species[0] and on the public's willingness to pursue those advancements.
Also, spaceflight is an immature area of knowledge, so one could argue that in general, each dollar put in it has more marginal benefit than the same dollar put into buying typical consumer goods.
--
[0] - Which is arguably not ever-increasing; we've pretty much lost the manned deep spaceflight capabilities with the end of Apollo program. There are practical details we need to rediscover, and those details will be important in efforts to put humans on Mars and elsewhere in the Solar System.
https://twitter.com/RichardGarriott/status/83632784187673804...
Sending humans to space has a very important non-scientific factor - human emotions and imagination. It's an important driving force that's also necessary until we bootstrap a proper profitable market that'll do the driving.
Imagine it ends up being some celebrity, like Leonardo di Caprio (who has shown interest in space IIRC) or Lady Gaga. Don't you think it would somehow tarnish the whole thing?
Either the rocket would blow up on the pad or it would never come back. ;)
Also, hopefully not Matt Damon.