Power is one of the few instances where "Build it and they will come" is nearly always true. :)
We can always find a way to use more power.
Nice review. Just like with people, if DARPA is not failing, then they are not trying. So I see "failures" as a good thing. Also, like in the SpaceX example you provide at the end, a lot of these failed attempts have spin-offs that lead to successes.
Cool stuff. I was in grad school at the time for planetary science. I would have loved to see that. I was a big DC-X fanboy. I wrote the project and they sent me back a nice letter and a marketing video on VCR tape, that I still have. Maybe I'll go fire it up for old times sake. :)
Your analogy is not a good one. Did you replace the filter on your shop vac between every single use? If so, it's refurbishable. if you didn't it's reusable.
You are mixing up shielding for protons from solar particle events with shielding for galactic cosmic radiation, which you can't really shield from. And the preferred shield material is polystyrene and water, basically anything with low molecular weight that will not create a shower of secondary particles, which is the third radiation threat.
Thanks for writing this article. I had been commenting the exact same on Twitter ( @ComSpaceNews ) about nitrogen being the most important gas for terraforming. Also, I think the radiation risks on the surface of Mars are overblown. You can't really shield effectively from galactic cosmic radiation due to the high mass and speed of those particles. The atmosphere does little to protect, even on Earth. The shower of protons from solar particle events are the greater concern, and those can be shielded against. Moreover, they are the biggest threat during transit from Earth to Mars. On the Marian surface a couple meters of regolith over the habitat should suffice. You could even have windows, as long as they weren't facing up (no skylights). Last, GCR do not leave a "trail of dead brain cells behind". They leave a trail of DNA damage behind, most or all of which gets repaired.
Nitrogen ice miner... It's tough work, but the pay is great!
I don't think the Old Space companies had much to do with this. Gateway is and was driven by the idea of using it as a testbed for technologies to take us to Mars. If you google DSG you will see the architecture that shows a stepwise approach to Mars. The moon is the obvious (and necessary) place to test technologies meant to take us to Mars, the least of which is propulsion. The lunar stuff is an add on, which is fine, and maybe a good primary goal in and of itself. The Gateway architecture may be successful in that it combines several existing diverse programs into one, and is thus harder for congress or a president to kill off or alter greatly. In many regards it is reminiscent of Zubrin's Mars Direct strategy, which is one reason I like it, and I think it has a chance of succeeding.
NASA is the same as it ever was, which may be good or bad depending on how you look at it.
The plan has always been for NASA to shunt off transport of crew and cargo to commercial companies. That part is going well. Commercial partners lift nearly all cargo to the ISS. Crew transport is in the near future.
This frees up NASA to devote more resources to the development of deep space infrastructure, which it is doing with the Orion, SLS, Gateway and other programs. I'm no SLS fan, and I think NASA could get more done in the other areas without it, but SLS and these other programs are generating a HUGE amount of new technology. Not to mention the fact that NASA is footing the bill for large parts of commercial vehicle development.
It's always amusing to see the arm chair quarterbacks on this site pontificate about how NASA is dead. I assure you, NASA is alive and well.
Most of your comments are wrong.
SpaceX is ALREADY contracted to take crew to the ISS.
SLS was never intended to go to the station. That would be like using a freight train to pickup a gallon of milk at your local store.
NASA is alive and well, and running a robust ISS program, with other programs in various stages of construction.
Your comments show some amazing ignorance of US space efforts.