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The Best Near-Term Future of Space Exploration?
An anonymous reader writes "Much fanfare has been made about manned missions to moons and planets, but little has been done about travel to the asteroids — until now. NASA is working on plans for a trip to the asteroids by 2025. This type of mission has great potential for positive economic return based on the fact that no effort has to be spent on getting in and out of a distant planet's gravity well. Yes, we should go to the planets, but we should master mining the asteroid belt for resources first because it is easiest. What do you think?"
If your goal is to set up self-sufficient colonies independent of Earth, the asteroid belt is the best place to do it. But I don't think it will be economically rewarding without our lifetime.
I've abandoned my search for truth; now I'm just looking for some useful delusions.
Rare earth metals, the easily mined deposits of which our civilization will probably have depleted in the next 50-100 years. Already there are serious concerns about switching to renewable energy sources based on the low availability of certain key resources.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
I think you can go down pretty damn deep before "easily mined" from asteroids becomes more cost effective than "easily mined" here on Earth! You need to mine the asteroids for resources to use in orbit, not to send back to Earth.
I've abandoned my search for truth; now I'm just looking for some useful delusions.
Mining stuff here on Earth makes a mess of our environment (more so in some places than others; here in the Arizona desert, it pretty much just results in an ugly pit, but in West Virginia, mountaintop-removal mining causes all kinds of ecological problems).
Now people (like China) are already talking about mining the sea floor, because we've depleted everywhere else. The sea floor is a much harsher environment than space for humans; in space, you just need to design a vessel that can contain a measly 1 atmosphere of pressure. Sending people underwater is much harder since you have to design your craft to keep hundreds or thousands of atmospheres of pressure out. Of course, you can do a lot of work with ROVs, but there's still a lot of technical challenges there because of the depth, and the presence of (very high-pressure) water all around. Space is relatively easy to work in. The only problem is getting out of our gravity well.
Digging deeper into the crust isn't exactly safe, either. Ask the miners in Chile who are still trapped underground.
Excuse the vent, but NASA has become lame as hell nowadays. What happened? From the space race in the 60s forward 50 years to now, isn't anyone else disappointed? I'm 31, and I was so excited growing up in the 80s, I couldn't imagine what I was going to see. Now, it seems to have all slowed to a crawl. Sure, Hubble gave us some amazing photos and scientific data, but where have the grand leaps and bounds in technology and sheer drive to explore been? Now, we have Obama hamstringing the space program as well, cancelling programs left and right. 2025? Ill be nearly 50, and I'd bet yet to see a man on Mars. I guess I assumed it would happen in my lifetime, and much earlier, even by 2010 at the rate things seemed to have been advancing. The idea of this is cool and all, but I really hoped we would push the envelope a bit harder, like the good old days. Sorry, I guess I'm just underwhelmed and disappointed.
Why do you think metals? The best substance you could pull from an asteroid would be ice. Ice can be converted into fuel. Ice can be converted into oxygen. Ice can be converted into water. A good icy asteroid can supply three of the four main consumables of space exploration.
When our name is on the back of your car, we're behind you all the way!
I think the mining idea misses the point. This NASA plan is all about gaining experience surviving outside of low earth orbit.
1: Surviving without the massive radiation shield that earth's magnetosphere provides.
2: Surviving without an option for quick Earth return.
3: Surviving without near instantaneous communication with ground control, Major Tom.
4: Surviving extended exposure to zero-g (muscle and bone loss)
Well #4 has already been worked out a lot at ISS though the amount of exercise needed is significant (less mission time) and not perfect (still need to get strong again when back on earth).
Shall we start debating the need for artificial G via rotation?
Also #2 has been somewhat worked over with ISS, specifically the need for lot's of spare parts, redundant systems, and design for easy repair. What's not so well covered is, wetware repair. MedBay anyone? Is there a doctor in the house?
A very long time ago, in a galaxy far, far away (MIT, mid 1970's, when I was an undergraduate and a member of MIT"s Planetary Astronomy Laboratory of that era), I remember having conversations with Mike Gaffey about asteroid mining. I see a reference to Technology Review on asteroid mining from Mike in 1977, so I think this got all published; I don't have any TR's of that era around to refresh my memory.
I remember one interesting scheme, where you might take a m-type metallic asteroid (which is mostly iron, nickel, and other useful metals) to earth orbit, by any of a number of propulsion schemes (solar sail, ion engine, or the like). It would probably take a number of years to move it from the asteroid belt to earth orbit. Then foam the asteroid (use solar mirrors to make it molten, and inject gas), and shape it into a lifting body. Then you would fly it into the earth's atmosphere, and land it in the ocean outside any port you would care to deliver it to. The point of foaming it was to reduce its density so that it would reenter the earth's atmosphere without much heating and ablation (we don't want to dump lots of metal into the earth's upper atmosphere), and float when you landed it.
Then you take a tug boat and pull it to a dock, and you have however many kilotons of metal you like. And without the huge energy cost of mining and environmental problems on earth.
As I remember, all the physics work (without having to invent fundamental new technologies), and there are lots of metallic asteroids. Now we just have to figure out how to actually do it. And it is way, way easier to deal with getting to and from the asteroids than the moon or any planet.
- Jim
This type of mission has great potential for positive economic return based on the fact that no effort has to be spent on getting in and out of a distant planet's gravity well.
Someone is forgetting that one has to get in/out of EARTH's gravity well which is the biggest one outside of the gas giants. Then you have to actually mine whatever it is (which we lack the technology to do) in deep space and safely bring it back intact. What are you going to mine in any serious quantity that you can safely return to earth without the item either burning up in the atmosphere or turning the item being returned into a weapon. (Remember that any significant fraction of an asteroid makes a heck of a divot when it hits the earth at high speed.) I can't imaging there are a lot of asteroids composed of precious metals floating around. Maybe there is an asteroid filled with inkjet refills or human blood?
Seriously, even ignoring the technical issues (which are huge) I haven't heard anything relating to mining asteroids that remotely makes economic sense. What could we possibly mine on an asteroid that could be worth the enormous cost of retrieving it from the asteroid belt? We only have a vague idea of what many of these things are composed of and what we do know isn't anything terribly rare here on Earth. The idea of mining asteroids is a romantic and cool idea but we would have to be SERIOUSLY in desperate need of something to make the economics of asteroid mining make any kind of sense.
Scientific research? Hell yeah. Economic return? Not likely in this century.
What was cancelled to make room for the asteroid mission was the Mars mission. Why? Well, the administration says that the asteroids are closer. I Am Not a Scientist (IANAS), but through careful and methodical research I've determined that the moon is still closer. And it likely has minerals, has some gravity to help with biological issues like muscle atrophy, etc. Oh, and we've already gone there with 1960's technology, so it's a pretty close bet we could do it again.
The current big problem is getting mass to (or out of) orbit. If you want to pretend the government's best role is things like infrastructure, they should fund private companies to develop heavy rockets for lift, space factories for building space-launched rockets, or a space habitat that isn't in low Earth orbit.
My suspicion is the asteroid mission was selected because failure (or future cancellation) will be hardly noticed. However, everyone would certainly notice a habitat on Mars or the moon that we no longer use. The saying goes "If we can send a man to the moon" not "If we can rendezvous with an asteroid!"
Finally, there are no intermediate goals in the strategy. Just "get there." What we don't need is NASA to wander about for years developing "stuff" with no progress. We've already seen that for too many decades.