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Fri 19 Mar, 2004 05:31 pm
Asteroids annually miss Earth by 100,000 miles or there about. Most of these have small dimensions less than 100 feet and/or are traveling more than 30,000 miles per hour with respect to Earth's surface. 30,000 miles per hour is about the fastest speed possible with chemical rockets without a sling shot maneuver = a gravity assist maneuver. We can launch from the surface or from ISS = the international space station with a crew of two and land on the passing asteriod less than one day travel time, and on very short notice, by stretching present technology only a little. Opportunities to return to Earth safely likely will not occur for decades, so I am proposing the first human colonies beyond low Earth orbit. Unmanned supply craft can be launched by the dozens before the first human colony in (mass center is best for radiation protction) an asteroid, making a rondezvous with supplies an annual or oftener occurence. Hopefully each asteroid colony would soon have several decades of essential supplies.It is not realistic to think two adults and a few children (born in the asteroid colony) can produce more than a few items of usefulness from asteroid materials but they likely can refuel the supply rocket for transporting themselves to other asteroids that pass close by.
Their main entertainment would be communicating on forums such as this one. Chatting would be impractial, when the asteroid was 1 to 15 light minutes from Earth, which would be nearly always. The main mission would be to chart asteroids which may sometime threaten Earth. Each asteroid colony could be equipped with a laser array for heating asteroids that needed an orbit change to avoid hitting Earth. If the effective range of such a laser array is less than one million miles, then we need a very large number of asteroid colonies as the present laser arrays can likely only change the orbit of a target asteroid about one second of arc per day, and a killer asteroid would rarely be within range even one whole day, plus the colony likely has less energy stored than needed for a day of firing the laser array. Neil
This is a proposal? Okay, I accept. But I will need funding.
Since you refer to colonies "in" asteroids, are you contemplating hollowing them out, and, if so, do you think that that technology is within near future reach? Also, I'm not sure how heating an asteroid will alter its trajectory to avoid a collision with the Earth. Wouldn't heating it harm the inhabitants?
I'm thinking very small scale habitats, which could be excavated with light weight machinery, perhaps manually operated. If digging is difficult, the two colonist might have to settle for a shallow habitat only a few feet below the surface. 100 feet is probably optimum as this would provide near perfect protection from radiation including any laser beams used to nudge the asteroid into a slightly different orbit.
Ideally the laser heats only a tiny spot so that it vaporizes some of the asteroid material which becomes ejection mass propelling the asteroid in the opposite direction. In asteroids less than 200 feet small dimension, the asteroid needs to be banded to prevent the habitat from expanding the asteroid to destruction. This is because very small asteroids have almost no gravity but the habitat needs at least 3 psi of oxygen for the colonist to breath. 300,000 square inches is a tiny habitat, but totals 900,000 pounds of pressure trying to expand the almost weightless asteroid. Neil
And what would be the point of such colonies?
neil wrote:...including any laser beams used to nudge the asteroid into a slightly different orbit.
Ideally the laser heats only a tiny spot so that it vaporizes some of the asteroid material which becomes ejection mass propelling the asteroid in the opposite direction. .
I'm thinking that this is an inefficient method of propulsion and possibly dangerous to the inhabitants, both because of the heat, and because of any damage to the asteroid. I would suggest ionic propulsion because it's already in use, and can deliver small thrusts for very long periods of time with high specific impulse (fuel efficiency).
Setanta wrote:And what would be the point of such colonies?
Good morning.
To me, the long range goal of space flight is to colonize other solar systems and turn the human race into a spacefaring civilization. This is a long way off, though, so now we need to develop the techniques involved. Therefore, I tend to look at any particular space project with two criteria in mind: (1) Does the project provide any inherent benefit? (2) Will it serve to help man perfect and practice space travel and settlement methods, so that someday we will be ready for interstellar colonization?
To me, one of the main points of putting men into space, is to get good at it so we can put more people further into space.
I don't have an argument with those theses, i simply do not see any value for the process inherent in colonizing asteroids.
We have been spinning our wheels for 33 years since humans have been more than a few hundred miles from Earth. We can return to the moon and be 270,000 miles from Earth or at less cost and perhaps less danger we can be a thousand times farther from Earth in an asteroid habitat.
We can send robot craft to chart asteroids that may threaten Earth. The robot can fire lasers at the potential killer asteroid to change a likely hit to a likely miss of Earth. I would feel better about a semi-competent human monitoring the course change from one or 6 light seconds away instead 1 to 15 light minutes away back on Earth.
We need to do things in space to develop proficiency. We can do asteroid colonies this decade. We may not be able to go to Mars safely next decade. Neil
I agree the asteroids with habitats should be equipped with an ion engine (or equivalent), but there will be millions of asteroids without habitats. The asteroid inhabitants will be working on ways to land on the potential killer and instal an ion engine. Likely doable with a human or two; more difficult robotically. Neil
If it is later determined that an asteroid with a colony is going to hit Earth or anything else, a slight risk of getting scorched by the lasers or having their asteroid fall apart due to the laser heating, will seem minor compared to a collision. Likely an ion engine or equivelent can prevent the collision and using a laser on an occupied asteroid will be a back up contingency. Neil
At the moment human space exploration is a technology without a purpose. We do not know enough about what is out there to have a purpose for going. A useful analogy would be the settlement of North America. It took over 100 years after discovery before a reason for settling there was found. The lag between discovery and settlement is going to be similar, if not longer for space.
Acquiunk wrote:At the moment human space exploration is a technology without a purpose. We do not know enough about what is out there to have a purpose for going. A useful analogy would be the settlement of North America. It took over 100 years after discovery before a reason for settling there was found. The lag between discovery and settlement is going to be similar, if not longer for space.
We know that there are a couple of hundred billion stars in the Milky Way Galaxy, and that about two thirds of them likely have planetary systems. We know that there are places to go, things to see, and probably people to meet (or avoid). We can reasonably assume that there are strange new worlds, and wondrous things to behold and learn. We also know that the Earth is Mankind's cradle, but that a baby cannot stay in its cradle forever. For me, this is enough. Let's go.
If a catastrophy kills all humans on Earth, some of the off planet colonies may survive and repopulate the Earth. Neil
Sharks with laser beams attached to their foreheads!!! All I ask for is sharks with laser beams attached to their foreheads! Throw me a frickin' bone heeeere.
Neil, are you still upset you only came in 2nd place at science fair/7th grade?
neil wrote:If a catastrophy kills all humans on Earth, some of the off planet colonies may survive an repopulate the Earth. Neil
why bother?
Seriously. I'd rather have all of us alive and un-struck by cataclysmic disasters, of course. But if something happens that will wipe out all of earth's population, well, thats the end, everybody's dead, nothing to be done about it.
You can't bring the dead back or restore the societies that will then have been destroyed beyond the hope of resurrection. You'd have to start right at the very beginning again, on an Earth turned wasteland, with a couple of lonely survivors in a world barren of everything they loved. Why? Why would that be a good thing? What inherent good is there in the survival of our species, beyond the desire to save the lives people live now? Those will have gone, for good. Why want to start the whole cycle up again?
Sharks with laser beams would be pretty cool tho. Imagine the aqualightshows!
The point to me is to develop space travel technology, and techniques of living off the Earth, so that at some point in the future Man can become a spacefaring civilization and do the things that are inherently worthwhile, e.g. mining the asteroid belt or exploring other solar systems (unfortunately far in the future). It seems to me that Man's ultimate future is in space. The problem is that we will never get there if we don't start.
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