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Old October 1st 17, 02:12 AM posted to sci.space.policy
Fred J. McCall[_3_]
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Default NASA is teaming up with Russia to put a new space station near the moon. Here's why.

Jeff Findley wrote:

In article . com,
says...

On 2017-09-29 12:42, wrote:
Op-ed: The Deep Space Gateway would shackle
human exploration, not enable it:



And on Friday, Elon Musk unveiled its "versatile" BFR that can, with a
single rocket, fly people New York to Sydney, bring people/cargo to ISS,
land on Moon and land on mars and return.


That part of the presentation is quite "far fetched" since it's not
likely "average citizens" would ever utilize it. It is, however, quite
possible the USAF would be interested, since this sort of thing has been
proposed since the 1960s.


Musk has since said that in the 'aircraft replacement' mode passenger
tickets would run about what a current economy class ticket costs now.
With an internal volume similar to an Airbus 380, you could presumably
stick 850 or more passengers in there for a flight of that short
duration. If we assume 1,000 passengers paying $2000 each (numbers
which are at the high end), that says a launch cost of only $2
million. That doesn't seem doable to me.


No talk of moon orbiting station. But rather moon base Alpha. (although
didn't quite look like the real moon base Alpha).


This is surely to attract the attention of NASA and other international
partners since NASA's proposed "deep space gateway" does not include a
lander (too expensive and time consuming to develop using the same
approach as SLS/Orion).

More importantly, Musk aims to have in-orbit automated refueling, not at
a station.


That's always been part of the plan for BFR. Otherwise, it can't go
much of anywhere once it's in LEO.


Launching a dedicated tanker or tankers as needed has always struck me
as a better approach then an on orbit 'gas station'. In the case of
the former you launch the fuel to the optimum location for a given
mission with no need for long term storage on orbit. In the latter
case you have to launch fuel to your 'gas station', which may not be
in optimum location for a given mission, then launch your vehicle to
that station to get 'gas' that you've had to store long term on orbit.
Dedicated tankers is easier and cheaper.


First flight to Mars 2022 or 2024.


Maybe, but not likely. Surely this will slip to the right by a few
years.


Musk said 2022 or 2024 because "five years strikes me as a long time".
I think it will take twice that, so call it 2028-2030.


Basically, once he has enough stockpiles of Falcon 9s and Falcon 9 heavy
that are re-usable, they can focus manufacturing on BFR.


This is true, and should happen within the next few years. They'll
still have to build a few Falcon parts, like the upper stage and
fairings (since they've not yet been successfully recovered).


Musk is still talking about getting a reusable fairing. That leaves
the upper stage.


**IF** this were to happen, it would blindside NASA into oblivion.


It would in all likelihood be an SLS killer. BFR could be used to
launch pretty much anything that SLS could. This would surely include
Orion as well (launch it in the payload bay, then transfer the crew to
it once it's in LEO).


BFR could launch anything that even Block 2 SLS can lift. Right now
Block 2 SLS is just a gleam in NASA's eye. I'm not sure why you'd
bother with Orion, given that the 'ship' part of BFR is orders of
magnitude more capable.


**IF** there is ay realism to this project, I can understand NASA
scrambling to find some project to remain relevant.


There is as much "realism" to it as there was to Falcon 9 launching
manned Dragons to ISS 5 to 10 years ago. Today, that looks imminent.

There is a lot of risk here, but the "holy grail" of cheap access to
space has always been a fully reusable launch vehicle. BFR, even if
unmanned, would be hugely useful.


It's almost too big. Replacing Falcon 9 with BFR (which Musk says is
the plan) is an insane increase in capability and the cost to launch
BFR can't be more than Falcon 9 per launch (around $63 million
expendable or something like $40 million with booster recovery).


--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw