Yes and no... on the surface of a "planetary" body, you can "sink" the waste heat from your reactor, but in free space, you need acres of surface area to dissipate it. I'm not sure if anyone has ever studied the trade-space between photo-voltaics and space-nukes, but I suspect it would lean toward high-performance PV cells, at least for cis-lunar operations.

Nonsense. They scale at least linearly, which is "good enough for gub'mint work" as the saying goes. I follow the "space" space fairly closely, and I've never heard anything about ion propulsion suffering from "scaling" problems. If you have sources for this, please cite them. As an avid enthusiast, this is the kind of information I crave above all.

True 'nuff, but for interplanetary missions there's no off-the-shelf tech to beat it. As Clarke said, "Once you're in LEO you're halfway to anywhere..." (or was that Asimov... or Heinlein?).

The thing about SpaceX is they're planting a flag on Mars now, and working back from there to define their technology. Their MCT (Mars Colonial Transport) engine class is spec'd to run on methane, since it's fairly simple to create this fuel from available resources on Mars. Nobody would be working on methane-fueled rocket engines if they didn't have a long-term goal of colonizing Mars.

Just had this "problem" the other day... I squeeze the bottle and nothing comes out, so I squeeze harder and harder until suddenly I hit the "breakthrough" point and get an avalanche. I do not like those squeeze bottles, thank you very much, the glass bottles work much better for me.

There's a very simple solution to the ketchup bottle problem: turn it sideways.

Most people hold the ketchup bottle vertically upside down over their plate and slap the bottom to make the ketchup come out. This doesn't work very well. Instead you hold the bottle horizontally over your plate and hit the side, so that there's plenty of room for air to enter the bottle while the ketchup flows out. Works every time. Try it.

Such "laws" (a la Asimov) are unworkable for the same reason that prohibition failed... there's always going to be someone who wants to disobey the prohibition for personal profit of some kind, whether as a consumer or a provider. As long as there is demand, it will be supplied, "laws" be damned.

I agree, at least to the degree that they're "obvious"... ie, the HUD/glasses form factor is the culprit. You look like a Borg, it's kinda creepy, etc.. But to me the most attractive aspect of G/Glass was simply its ability to record my movements throughout the day, like a policeman's lapel-cam. At the end of the day, I could save a few highlights, and clear the buffer, like a diary.

As for the HUD display, augmented reality is overrated, If I need "augmented" info in real time like that, I'll get an iWatch instead. However I do like the idea of a "body-cam" to serve as a record in case something happens. And this could be done with clip-on, blue-tooth jewelry (perhaps in a "swarm" for 3D capture) instead of a face-mounted camera-cum-display gizmo.

So yeah, as TFA says, they'll "save the technology" for later use..

Looks like a very interesting book, thanks for the link.

My point was that Mars-One doesn't have to bring down costs because the industry is already doing that. Lansdorp is just betting that the costs will be within reach by the time he has to start bending metal. That gives him a few years, realistically, to ramp up the TV show and start generating some revenue. In the meantime, SpaceX will have upended the launch industry with the advent of reusability and Dragon.V2 will have flown astronauts to the ISS. You have to view it in that context, not the current one.

Do I think Mars-One is a bit "too visionary" to ever become reality? Yeah, of course I do. But that doesn't mean it's impossible. It's not possible today, certainly, but I think it is possible -- just barely -- in the long run, and I'm sure Mr. Lansdorp agrees.

Also, I'm sure I don't have to remind anyone here what most folks thought of that wooly-headed visionary Elon Musk about 13 years ago...

Ditto.

Obviously they didn't have SpaceX's capabilities available when they approved the Curiosity mission over a decade ago.

Having a rocket thruster that can ignite in supersonic mode is a game-changer, especially for Mars. Most people in "the business" didn't think it was possible until SpaceX proved them wrong. This is just another example of folks not realizing how much the game has changed while they weren't paying attention.

We are on the brink of massive changes in aerospace... I just hope enough people will "tune in" before it's too late.

Remember Viking I and II? They didn't need complicated airbags/sky-cranes and such because they used a "brute-force" powered landing just like Apollo. But SpaceX now claims to have a Super-Draco thruster that can ignite under supersonic conditions... IOW, SpaceX claims it's Dragon.V2 capsule can land propulsively on "any surface" in the solar system, including (especially) Mars. Based on recent performance in the last few years, how much money would you be willing to bet that Elon Musk is wrong about this?

This is where the reusable booster comes in handy... if your limiting factor is fuel, then just use multiple cheap launches to assemble the hardware and fuel on orbit before trans-mars injection.

I can certainly understand the skepticism, but I think a lot of the skeptics are not up to speed with the latest in NewSpace. For example, SpaceX is on the verge of proving the viability of reusing booster stages... that alone will drop the cost-per-pound to orbit by an order of magnitude.

There are dozens of companies such as Masten, Sierra Nevada, Armadillo, XCOR, MoonEx, Bigelow (etc) some of which have been profitable for many years, working on various aspects of the overall project (for their own purposes of course), such as RCS thrusters, GNC avionics, spacesuits, hab modules, etc.. So a lot of the stuff Mars-One will need is already available off the shelf, and at a much lower cost than NASA has traditionally paid in the past.

Comparing Mars-One's plans to past experience is an apples-to-oranges comparison. You have to evaluate their plans according to what can reasonably be expected within the next half-decade or so.

Exactly. As Elon has noted many times, when you have to forcefully recall your product from unwilling customers who then go on to hold a candle-light vigil for the destruction of their cars, the "market" is not a barrier to your product... you're doing all this because you want to kill it, pure and simple.

Perhaps the market was small and upscale, but it existed, and it was strong. GM could have pursued development in this space, but it vehemently decided not to. Tesla just picked up that residual demand and built on it.

As DSI and PR get up to speed, we're going to have an avalanche of data to process. As long as they're willing to give back, I'm happy to donate some CPU time to their efforts.

But there's a whole 'nuther layer of potential... having amateur astronomers net-link their instruments to the overall effort... what kind of pinpoints could we arrive at by crunching the numbers from thousands of points on our globe?

LOL!! The Fed may be independent of gov't but it's not independent of corporate plutocracy. Indeed, this is the crucial struggle of our times, wresting control of our politics and our economy from these fat-cat SOBs.

Get thee hence to Wolf-PAC.com and pitch in to help save our democracy from these blood-suckers.