Human Missions to Asteroids

There's no way we should send astronauts out to an asteroid without the proper shielding to protect them from a potential solar flare during the journey to and from the asteroid.

Besides, there are plenty of small asteroids we could capture by unmanned light sails and bring back to a Terra-luna Lagrange point for processing into oxygen, water, and hydrocarbon resources.

Marcel F. Williams

"You have to have a big rocket to go to Mars." said McDaniel

If you say so, and everyone repeats it enough. What goes for conventional wisdom at Marshall, and elsewhere...

use resources trapped in the floating rocks ... setting up a "gas station" or depot in space.

Funny that author Shelby from Huntsville is enthused that a NASA-mined fuel depot far away in the asteroid belt necessitates an Ares 5 launcher, yet ignores what impact a fuel depot in low Earth orbit would have on the same heavy lift vehicle.

Getting fuel from asteroids would be great at some point in the future, but right now fuel depot technology is a long way from being operational, and technology to mine asteroids and make fuel is even farther from reality. I hope that whatever NASA does, technology development doesn't get neglected.

"Keith Cowing, a longtime NASA critic"
Really! Why not "experienced NASA analyst" or "NASA watchdog" Why is everyone a critic?

Ahem.
The article is so packed full of basic errors one does not know where to begin! From the: "basically a big chunk of rock in space" to describe a complex set of bodies ranging from organic snowballs; through cosmic dust bunnies to earth flattening bollides of metallic death!

Missions to NEOs (vs Phobos and Deimos) are once in a generation, if we rely on chemical fuels. Three, maybe four, up to 2068: 2001 GP2 departing 2020 (note needs LOTS of dv and the infrastructure may not be in place); the oft quoted Korsmeyer study (NASA Ames) 2000 SG344 (in 2028) and the cheap and cheerful 1991 VG (2068). Fourth? One we probably haven't spotted yet. Some of these NEOs are just meteors with pretension to grandeur. 10m plus.

No NEO mission 'needs' an Ares V. What they do need is a reliable ECLSS and effective radiation mitigation. A VASIMR propulsive stage would help!
For further reading I would suggest starting here:
http://www.thespacereview.com/article/838/1

A final parting shot: "The probe [NEAR] was a technology-development mission to prove that an object could be placed on an asteroid." Twaddle. That part of the mission was pure expediency they wondered if it could be done and thanks to some pretty neat orbital mechanics they 'may' have pulled it off. Unlike the author of the article!

why not bring the asteroid to the astronauts? that is, a tugboat mission that would harpoon an asteroid and tow it back to the ISS for in-depth analysis.

We don't have the means to move a rock worth study. Even if we did, you'd be dragging something big enough to be dangerous into low earth orbit... some folks might object to that.

While I believe that in rocket based space programs, bigger is better, I also think the idea that asteroid missions are naturally cheaper or easier is a fallacy.
We would be approaching targets with very little lead time and most of the ones we're interested in are fairly distant. Going out to touch one in person with so little information is begging for trouble.

We will have to do a bit of homework to make these missions happen. These projects will come with their hidden costs.

The NEOs are just rocks. (Yes, I know all about asteroid types, and I know all about the scientific importance of asteroids.) They're NOT PLANETS. Not even I can work up any real interest in them...and if I can't, the public certainly will have none. One of the big main-belt asteroids might be a different matter.
In any case, we all know that this latest New Improved Space Program will come to nothing, just like the last one. We'll study it for a few years, decide that it's a bad idea after all, study something else for a few years, and on and on...

NEOs can have interesting compositions. The mission is worth the effort, I just don't think this is a mission you build the entire space program around.

I would more continue on the path to moon or mars then pull one of the landers from the production line. Strip off its moon centric equipment, replace it with supplies and fuel, and pre-stage that stack for launch on the next opportunity.
By reprogramming surface landers for asteroid chasing you can do both kinds of exploration missions for little extra cost.

The only problem is part of the rationale for doing asteroid and NEO flybys is NASA can't afford building Altair...

The Augustine Committee set a bold and audacious goal for human exploration, "to chart a path for human expansion into the solar system." This will require two supporting objectives: (1) physical sustainability, and (2) economic sustainability. The first requires volatiles to provide oxygen, water and rocket fuel. The second requires valuable materials such as precious metals that bring jobs and wealth to Earth. As far as I can see, neither objective can be met down the deep gravity wells of Mars or the Moon. The fractious space enthusiast community's continued focus on the Moon and Mars is (as Spock would say) "illogical," driven more by science fiction fantasies and our inborn biological need to know which way is up. Our descendents will explore and colonize Near Earth Objects (NEOs), Phoebos and Deimos, and the asteroid belt, and/or build habitats from their materials, long before they ever swallow the risks and expense of walking on Mars. The need for economic and physical sustainability set corollary technology development goals to develop in-space extraction methods. The first NEOnaughts should be called prospectors, and the first human missions to NEOs should be named Prospector I, II, etc. The first platinum returned could be minted as coins to add collectors' value to help pay for the missions.

I understand what you're saying about Mars, but surely the Moon isn't without practical advantages?

What about the fact that the Moon is always near? The ability to remote control robots in real time from Earth means the ability to have a very large number of advanced robots without the need for AI or any high power computers on-site - which as I understand are not trivial to deploy to space. (Isn't the 200mhz RAD750 top of the line?)

Besides, the challenge of getting to orbit from the Moon isn't _that_ great if you can fuel it on-site. I mean, the LEM did SSTO with hypergols. Its not like you're landing on Venus.

Actually, I'm more agnostic about the Moon, but very antagonistic about all the Mars hype. If Mars is the goal, I'm actually afraid we WILL get there, just as we did with Apollo and the Moon. We'll walk around a bit, collect some rocks and come home again, and then wait another 50 years before the world get up the energy to leave LEO again. As for the Moon, with a three second time delay we could tele-operate equipment and machinery there and never have to go in person (which probably cuts costs by an order of magnitude or more). Would that be such a bad thing? What is the business plan to extract value from the Moon, profit to make our presence there economically sustainable? I guess I'm drive most by the high siderophilic metal content of some asteroids, and the very low delta V needed to get there.

Not going there in person wouldn't be such a bad thing. If we don't have to land people, that would make utilizing the Moon a lot cheaper.