The “Easter Egg” habitat, as I’ve conceived of it, has a solar collector at one end which both collects solar energy for use in maintaining thermodynamic equilibrium and powering the hydrological cycle (as well as other energy needs of the inhabitants) and shields the habitat from direct solar impingement. By not having the power supply inside the habitat, the need to reject waste heat becomes much easier to handle, and with the large thermal mass of both liquid water and solid water ice mediating the temperature conditions requires relatively little effort; such a system could be designed to be passively self-maintaining on the order of weeks or months without any human or automatic controls. However, it will require regular replenishment due to both loss of mass through sublimation (though at a very slow rate) and reduction of other elements and raw substances. Being able to maintain the structure for the tens of thousands of years it would realistically take to transit interstellar space to even the closest stars using any known propulsion methods is not feasible.
But then again, hauling around bodies and all of the necessary resource to maintain them through space is as impractical and unnecessary as trucking an RV up Mount Everest. Building such a habitat is just an interim step in adapting to living in space rather than just visiting it from time to time at great hazard and cost. I don’t expect we would ever ship humanity at large (in it’s current corporal form) from Earth into space; any problems with habitation or pollution are almost certainly more easily solved on Earth’s surface than in space, barring some kind of complete annihilation that kills off most of Earth’s population to begin with. The real value in developing space resources and habitats isn’t to ease population pressure or make money or whatever, but to allow humanity to begin its self-directed evolution off of Earth.
But this still has to be done on a fiduciary basis that makes it worthwhile to the remaining mass of humanity that is footing the initial bill (to the tune of hundreds of billions, perhaps trillions) of dollars before such habitats become self-sustaining; hence the need to provide valuable services such as Earth and space surveillance, rare or difficult to process materials, et cetera, back to Earth to justify the cost. And until such habitats exist, it is far cheaper to do the bulk of exploration and extraction via remote systems that don’t require the extra mass or energy of keeping a body alive.
I wish that they would beat us. Maybe it would light a fire under our asses and inspire us to take possession of the rest of the Solar System, like God intended.
No, I would no be upset if another country were first to send people to Mars. It would mean that at least someone is concerned for our future.
I can’t see any way that the Earth can supply all the resources needed for 8 billion people to live with standards of living equal to that enjoyed currently in the United States. And without an extreme change in attitudes about ecology, I fear that we may make this planet uninhabitable by humans.
After the revolution created by microprocessors, the images of the Earth in space from the Moon were perhaps the most important benefits from the space program. To see our home as it truly is was a huge shock to people all over the world. We have learned more about the Earth since we left it than we had in all the years previous.
Even if we assume for the sake of argument that that fear is not unfounded, do you fear that we will make this planet more uninhabitable than Mars already is? Because that’s just crazy talk.
The Earth is the only place in all that we can see where we can walk unprotected upon the surface. And even here, there are places where an unprotected human would not survive very long. But planets are a rarity in the Cosmos, so why should we focus our efforts on surviving only on planets? Stranger_on_A_Train described a habitat that could support humans without requiring a planetary surface.
Extracting resources from planets can be very difficult, so it is fortunate that most, if not all, of what we need is floating around in chunks of matter that are not in the bottoms of deep gravity wells. Because we will stop at nothing to acquire what is needed to make life easier, even if it puts that existence in jeopardy. Copper is one element that we cannot seem to get by without. It is fundamental to our technology, and no other element will substitute for it. Currently, copper mining is one of the most environmentally destructive activities humans pursue.
Finding and extracting copper from asteroids would be worth many times what a manned landing on Mars would cost, and the technology required would make going to Mars much easier. If we still want to go. Most of the interest in Mars seems to be romantic, not scientific. In all probability, we will find some kind of life on Mars, but so what? Life is everywhere on Earth, so it correlates that life is everywhere in the Cosmos. We have not been around long enough to warrant attention, if there happens to be any sentient creatures out there right now. We will have to solve our problems ourselves, we cannot expect some alien culture to step in and save us from our stupidity.
Any discussion of crewed missions to other planets is based upon one important assumption: That manned access to space will become much cheaper. Unless we can develop a reliable, safe, cost-effective way of reaching low-Earth orbit, exploration will have to continue via robots. Until recently, reaching orbit demanded taking off straight up. There simply were no powerplants available for an aircraft that could carry a spacecraft fully fueled to high altitude. Today, we have turbofan engines that produce several times their weight in thrust.
Using a number of these, which are like those used on the new, long-range jets, a wing large enough to lift a million kilograms could be built. Or, it might be biplane, with a second wing which is only inflated for the flight to altitude. But some way must be found to get away from launching straight up. Nothing can go wrong when launching straight up, which is why new rockets that are man-rated have not been seen. Even tried-and-true boosters such as the Atlas are not man-rated, because they lack the back-up systems required for such a rating.
We don’t need to lift a million kilograms to 15 kilometers to be able to send a dozen people to orbit. We can probably do it with half that amount of mass, as long as we focus on carrying people. Cargo can still go the old fashioned way, straight up.
There are some advantages to launching a space launch booster from a carrier aircraft as SpaceShipOne and the Orbital Pegasus vehicle have done, but significant gains in performance or reliability aren’t really key among them. Launching from a carrier aircraft does mean that you don’t need to maintain or clear a ground launch facility, and it also means that launches can be conducted at an optimal location and azimuth for the intended orbit, as well as possibly avoiding obstacles on the ground track. There is some savings as well in terms of the mass of the vehicle, as not having to loiter while the stage builds up velocity reduces the losses of so-called ‘gravity drag’ versus the efficiency of an air-fed jet engine and lift developed by forward motion. However, this also necessitates a sufficiently large carrier aircraft to carry such a shuttle, which is not impossible but is challenging. The Pegasus, currently the only space launch vehicle which is flown in such a fashion, is carried underneath a Lockheed L-1011 aircraft and can boost about 440 kg into Low Earth Orbit. A vehicle large enough to carry a small shuttle with a three or four person capacity and the booster vehicle to take it to LEO would need to have a lift capacity at least a couple of orders of magnitude larger. However, your essential point about separating the lower criticality cargo launches from the necessarily very high reliability of personnel launchers stands; the STS ‘Shuttle’ was an attempt to combine both functions to the detriment of either. A high reliability medium weight vehicle carrying only personnel and small cargo could be complimented by a lower reliability and performance (with correspondingly lower cost) superheavy launch capability.
However, it should be noted that even an improved capability to LEO is only one small part of human habitation and excursions beyond LEO, and in particular mitigating the hazard of high energy cosmic radiation, lack of gravity, and efficient recycling of consumable resources. The particular and as-yet unsolved problem of landing a heavy vehicle on Mars is also a substantial challenge equal to or greater than the problem of launching humans from the surface of the Earth safely and effectively, but is glossed over by enthusiasts who have not considered this issue.
Would it surprise you that my proposal is based upon NASA design studies in the 1960’s? These were incorporated in the first designs for the space shuttle, which bear no resemblance to the Space Shuttle. You mention the Pegasus booster, and how it is launched from a L-1011 ‘Swamp Buggy’. Only a purpose-built aircraft would be capable of carrying the required weight to launch altitude, one without swept wings or a fuselage.
And the take-off weight would be so high that launching from a track, or rail, with a catapult of some kind, would be required. No undercarriage would be able to support the weight. As well as needing a very thick runway several kilometers long.
The most difficult part of space travel is getting to space, because it requires accelerating from 0 kph to 7 or 8 kilometers per second! But we cannot do that anywhere close to the surface of the Earth, because the atmosphere is too thick. Rockets climb very steeply until they have reached 10 kilometers or so, and then they tip over towards the horizon and really start accelerating. Using an aircraft to carry the space vehicle to 10 kilometers means that the spaceship can be much smaller, as well as lighter. And most of the fuel used will be for accelerating, with only very little going into increasing altitude. The faster you go, the more altitude you gain, as the planet curves away from your trajectory.
Landing anything of size on Mars will require rocket thrust to cancel nearly all of the orbital velocity, which is several kilometers per second. Conditions on Mars are much worse than was speculated in the 1950’s and '60’s; The atmosphere is so thin that it might as well not even be there, except that it can pick up dust, as you have mentioned. Aerobraking is not very effective, and parachutes don’t slow things down very much.
Another aspect of horizontal launching with an air-breathing airfoil first stage is that the space ship never is in the state where if anything, anything at all, goes wrong, there is no way to pull over, abort and fly back to the launch site and land, or get by with less than full power. If there is a failure, then the part of the rocket containing the life forms must be separated from the rest of the rocket, and carried away from the rocket, by going even faster than what they are trying to get away from.
Flying off the back of a big wing would allow for the engines of the spaceship to be run up prior to launch, so that any problems might be resolved without having to abort. Launching horizontally is not in our vocabulary because doing so on the surface means wasting fuel, because you can’t go fast. At 10 or 15 kilometers, you can go fast, and the faster you go, the higher your vehicle will rise. But it would be nice to make sure that everything is working right before committing to going really fast. And have options that don’t mean destroying the spaceship to save the crew.
The problem of manned access to space is the single greatest barrier to rapid development off-planet. Until people can get into space in larger numbers, much more cheaply than they can today, development off-planet is going to be slow. Robot rovers are a whole world apart from what is needed to create an automated factory in a zero-gravity environment. Humans may not be outside swinging the picks and hammers, but they will probably be a lot closer than Earth. On the spot management, research, and adaptation are what humans are needed for, and working remotely-operated vehicles will become a trade in demand beyond the oil industry, where all work on the sea bed is done by remotes.
But I believe that there is a higher reason to reach out and learn about our surroundings, and it probably has to do with looking outward instead of inward, challenging ourselves to find out what is beyond the next ridge, valley, planet, solar system, galaxy. The desire to know is the most important trait that our particular form of life has, and is the easiest to lose. Space captivates our inner selves, opens our eyes wide, and turns us into children momentarily. Not very many things can do that anymore.
We can colonize Antarctica for the fraction of the price of Mars. It is warmer and much nicer there. Plus, you can always leave. Going to Mars is a one-way trip-and dying there is likely to be unpleasant.
This points out the fact that it is not population pressure which is pushing for colonizing Mars, but a small, but very loud, group of enthusiasts. They seem to have convinced themselves that Mars can be made nice somehow, and that it will be worth the tremendous distance from Earth to live on Mars.
What amazes me is the widely-held attitude that going back to the Moon would be pointless. What better place to experiment and develop the technology needed to explore and exploit off-planet? Between the Moon and some asteroids, we have tremendous challenges that rival what Mars will require; long term survival in a radiation environment, heavy equipment operations in an airless environment, utilization of solar power on a large scale, long range communications, new propulsion systems, the list goes on and on.
There seems to be a romantic obsession with Mars that bears no resemblance to the actual planet. Holding Mars up as our next goal in space hurts the space exploration effort, I believe, because there is so little to justify going to Mars to the man on the street. At least the Moon is a visible place, somewhere that you can be sure the listener has seen, instead of a point of light in the sky.
When travel to the Moon has become commonplace, and there are regular missions to intercept asteroids, then we will be in a good position to investigate Mars in person. Until then, I suggest that we continue our robotic exploration. We should at least wait until getting off of Earth is not such a big deal before we start talking about going to Mars.
Yes, it would bother me. I would prefer as a matter of patriotism, national prestige and history that the U.S. be the first to send a manned mission to Mars, as we were the first to do on the Moon. China is a one-party dictatorship and Russia is sliding in that direction; humanity would be better represented by the U.S., for all its faults. I would have no objection if it were an international mission, but would want the U.S. to play a key role.
I can understand patriotism.However China is one of the oldest civilisations on earth (and the inventors of rockets to boot) so dismissing them as a “one part dictatorship” seems…strange.
He said they are a one PARTY dictatorship, which is absolutely true and would only be strange to someone who hasn’t been following events or is being disingenuous or is simply ignorant of conditions in China for the last 60+ years. And that party has done a hell of a lot to stamp out China’s cultural heritage, including it’s history, so trying to claim it goes back thousands of years is a bit ironic in the context of a discussion about the CCP.
One of the things that Space exploration does is make human politics and ideology look petty, (as Carl Sagan noted). Except perhaps to petty people, (not that Elendil’s Heir is petty in the slightest from what I have seen here over the years).