Spacing Out Off Planet

Miscellaneous and Personal Stuff I Must Share
1

For some reason I cannot explain very well, I believe that humans need to expand the sphere of their activities beyond planet Earth. Earth should be an industrial free zone, where people can walk under the sky without spacesuits. We are creating eternal environmental disasters, such as open pit mines which flood with acidic, poisonous water. Extracting resources from the Earth in quantities to satisfy the demands of billions of Chinese, Indians, and South Americans will threaten our very existence.

Getting off of Earth into space means going very, very fast. Space is very close, only about 80 miles from wherever you are. You have to go a little higher if you want to stay in space, because there is still too much air resistance at 80 miles to stay in orbit. Air resistance is the biggest problem we have in getting into space, because there is just no way to go fast while in the atmosphere.

Progress has been very slow in learning how to leave Earth, because the only way that we have had to do that has been rockets. Rockets which take off straight up. So the technology is rather challenging, to say the least. The reason that the rockets take off straight up is so that they can get above the atmosphere as quickly as possible, so that they can start going fast. When I say ‘fast’, I mean miles-per-second fast. Like 5 miles per second to stay in orbit.

The bulk of the atmosphere is here, close to the ground. By the time that you have reached the height of Mt. Everest, you are above more than 3/4s of the atmosphere, in terms of density. But there are traces all the way up to 300 miles. The International Space Station has to be re-boosted every few months to make up for the altitude lost to air resistance.

Rockets are fighting the atmosphere for miles after they take off, because air is something very different to what you think of when traveling at mile-per-second speeds. In fact, the atmosphere is so dense even at 70,000 feet that airplanes can fly that high. Barely. So an airplane that carried a spaceship to 50,000 feet before launching it would save a tremendous amount of fuel for the spaceship. This is because the spaceship doesn’t have to take off straight up at 50,000 feet, but instead can head for the horizon.

Going fast means going fast around the Earth, not up into the solar system. A spaceship launching from the back of a carrier aircraft would be able to accelerate at full power, using lift from its wings to increase it’s altitude, until it is traveling fast enough that the ground curves away faster than the spacecraft is pulled down by gravity. The faster you go, the higher your orbit will be.

Okay. If we can put, say, a million pounds at 50,000 feet, we could get a spaceship into orbit that could carry a payload of about 20,000 pounds, maybe a little more. That is enough for 12 or 15 people, plus a crew of two, to go into orbit.

More in a bit.

2

Just lost about 1/2 hour of work because the site logged me out automatically after a certain time without my submitting anything. When will I learn? Always compose off-line, then paste! Idiot!

Goodnight, or day, or whatever.

3

You’re suggesting we embark on an extended program of launching spaceships off the back of aircraft carriers to get away from all the polluting Chinese, Indian and South American people?

Yeah.

4

Getting off earth and into space will involve the ability to clean up the environmental disasters that you mention we should avoid making.

Earth to me is the cradle of humanity, we will leave the cradle and be starborn one day, but till then we will need the care of mother earth to help us with our messes. And this is where we must learn to do that and learn better ways that do not cause such problems. So I don’t think it’s something to avoid, just something to learn on our road to the stars.

I also believe that the light barrier which is now a problem will be seen as a blessing once we find out how to exceed it which I believe we will, and will open the doors for efficient and fast IS travel. Because it exists we will need to overcome it and find new ways.

5

Agreed; they should stop aspiring to the standard of living we Americans enjoy.

As for the whole space thing - you may want to look into the cost and logistics. Here’s some light reading for you, and an obligatory XKCD reference.

TL,DR: interstellar travel is nigh impossible for human beings, and getting everyone off of the planet would bankrupt us anyway.

6

It would be great if we could put industry out in space far from earth or on the moon, say*. The problem (besides the Kessler syndrome if we’re not careful) is that we have to pollute the atmosphere in order to lob things up into space, and that getting things into space and back from there is expensive.

There are potential technologies that can make space more accessible – Space Elevators/Beanstalks if we develop sufficiently tough materials, or space pinwheels (as described by Robert Forward and others) that don’t require so much from their construction materials. Or LSD-wave Laser Propulsion as proposed by Arthur Kantrowicz and championed by Jordin Kare and others (if it gets to the point of using ice in place of more toxic materials). Even if the problems around these are solved, these are still very energy-intensive activities. Getting into space (and back from it) can be made cheaper, but it’ll never be truly inexpensive, as far as I can see. Plus there’s always the possibility for grotesquely expensive and destructive accidents.
Still, as Heinlein said, the surface of a planet is no place for industrial activity.

  • (putting industry into earth orbit will, I can practically guarantee, “pollute” space with the sort of garbage that we’ve already managed to get up there with our relatively rare and restricted space activities. Too much junk flying around at high and random speeds and angular orientations relative to the poles – as would result from increased activity, especially industrial activity – is virtually guaranteed to bring on the Kessler Syndrome that folks have warned us about, erffectively shutting off access to space.)
7

Never ceases to amaze me how a thread about getting into space will spark replies about going to Mars or the stars. There certainly are a lot of people who are anxious to leave Earth. Permanently. Me, I just want a way we can get off-planet that is safe, reliable, and as inexpensive as possible. And no, it does not involve aircraft carriers.

But it does involve carrier wings, which are aircraft which are designed with only one purpose, to lift stuff to high altitude. So there would be no fuselage, the wing would be straight, and it would have a lot of engines. Because, if we want to lift one million pounds, we will need an aircraft that weighs about twice that much. Which brings up the next question: How do you get something that big off the ground?

For starters, the aircraft would be too big to rest on an undercarriage. Additionally, a runway which could support that amount of weight would have to be very thick, and would have to be very long. An aircraft takes a long time to get up to take-off speed, and then there must be enough runway for the aircraft to stop if something goes wrong. So, instead of building 5 miles of runway 50 feet thick, we build a catapult.

This catapult will be powered by electricity, and will be able to get 3 million pounds moving about 300 miles per hour in less than a mile, hold it at that speed for a short period of time, and then slow it back down to a stop. The catapult would have a track that is elevated about 40 feet above the ground, and there would be a cart which rides on the track to support the carrier aircraft, which would have the spacecraft on its back. The cart would be attached to a big slug of iron, which is what the electric drive would react with.

The spacecraft rides on the back of the carrier wing for several reasons. For one thing, it will be too big to be straddled by the carrier wing. We are talking about something that looks a lot like the space shuttle, only somewhat bigger, as there would be no external tank. Another reason is that dropping the spacecraft before the engines are started results in a lot of altitude being lost before the spacecraft can pull out of the dive and start going fast. We want to start going fast as soon as possible.

Again, I remind everyone that this system is strictly for putting people into space, it would not be used, at least initially, for launching cargo. Cargo can ride on rockets, but rockets that take off straight up are too dangerous for people. That is why the only people going into space right now are riding Russian rockets designed in the 1960’s.

8

Rockets don’t really go straight up.

But I agree it would be great one day if we treated the Earth as a very important nature & wildlife park and biological reservoir. So far, it is the only known place in the universe with life on it, and that makes it pretty special, unless you’re an unfeeling computer.

9

Space elevator man.

Then we can all go back to our natural place in the environment as hunter-gatherers.

And chillin" …

10

Excuse me, but have you ever watched a shuttle lift off? Or films of the Apollo launches?

Rockets do indeed go straight up, at least initially, and they climb at a shallow angle after that, or they throttle back, as the shuttle did, so that they don’t go too fast. You may have heard the term ‘max Q’, which refers to the density of the air, which determines how fast you can go before the turbulence destroys your vehicle. The less dense the atmosphere, the faster you can go. The first five or six miles are the densest, but it still is appreciable at 8 miles, and aircraft can fly at altitudes much higher than that using aerodynamic lift, no rockets, just jets.

So rockets will arc out over the ocean, because, as they climb, they turn more and more toward the horizon. The higher they go, the faster they can go, but they still have a ways to climb before they can really start accelerating. The shuttle Columbia was still high in the atmosphere when it broke up, (the second shuttle loss caused by management decisions; the engineers wanted to stop flying until they could fix the foam problem, but management wanted to stay on schedule. Thus the several year delay before regular flights could resume. The only reason that the Challenger was lost was because somebody with a lot of influence in the White House wanted Christa Mcauliffe to be in orbit when Ronald Reagan held the State of the Union address.)

This is the reason that I am championing a two-stage to-orbit system, because using an airfoil for lift is much more efficient, safer, and reliable than vertical launching. Sure, we have never done it on any effective scale, but the dynamics of the process are well developed. We have never built a really big wing, because no one ever saw the need for one, plus, we did not have engines powerful enough to push a really large wing. Now, we have engines that produce several times their weight in thrust, huge turbofans, the kind used on the Airbus A380 and the Boeing 787. We could put 12 of them on a wing that would be longer than a football field, if we had to. I have been astounded at what the White Knight aircraft have been able to do with the power that they have had. Burt Rutan has obviously designed wings that were tremendously efficient without having much drag.

But the scale that I am envisioning would require a wing much more substantial than the White Knight aircraft have. After all, I am discussing launching spacecraft into orbit, not pops straight up and down. To lift a fully loaded spacecraft which weighs one million pounds, the wing is going to have to be very substantial. The wing might be more difficult to land than the orbiter, because it will be a big, light for it’s size, kite, which will be hard to land in a cross wind. There is a possibility that the launching catapult might actually be used to retrieve the carrier wing, as it can be controlled so as to match the wings velocity exactly.

Now that the private sector has gotten involved in developing space craft, we should encourage some investors to put some of the trillions of dollars chasing a profit into developing the transportation system that will be used for years and years, safely, reliably, and economically. This is a system which does not throw away anything, everything is reusable. This is a system which can facilitate rapid turn around of the carrier wings, so launches could be scheduled frequently. Eventually a carrier wing will have 5 or 6 orbiters that it services, maybe more, so that flights can happen weekly, or even daily. Crew rotation will demand dozens of people changing places on a regular basis, once investment in space begins.

The primary reason that we have been advancing so slowly in space technology is because of the enormous difficulty in launching people straight up safely. The secondary reason is that we are very limited in the number of people who can fly on a given launch. Unless higher staffing levels can be maintained, research and development in space is going to be severely hampered. It takes people just to keep a space station running, as well as the scientists who are doing the research. Right now, the scientists are the ones who have to keep the International Space Station working. They hardly have any time for real research.

11

The possibility of a space elevator ever being built are directly linked to the amount of investment that is made into space to create demand for such an exotic solution. Yes, it is the IDEAL way to get into space, but it may be beyond our abilities for some time to come, and it is definitely a pipe dream right now. There will have to be many breakthroughs in technology, plus a very large off-planet infrastructure, if a space elevator is ever to become a reality. I put the likely hood of one being built to be about the same as the likely hood that faster-than-light travel will ever be developed.

In the meantime, I want to see us doing stuff off-planet, learning how to live, and to work, in space. And I really believe that it will eventually be cheaper to get resources from space than it will be to get them from here on Earth. Especially when you consider that there are big chunks of just about every substance known to man floating around somewhere in the solar system. The solar system is kind of like a centrifuge, in that things have been spread out by density, with the heaviest stuff close to the sun, and the lighter stuff way out past the Asteroid Belt, which is where we are likely to find some of the coolest stuff.

And we need to get a camera going which can keep track of all the rocks floating around out there, because, every once in a while, one of them decides to drop in on us, and things could get really ugly when a big one does. Putting a satellite in an orbit around the Sun, about the same distance out as Venus, with a camera which can detect infrared would give us a picture of the solar system that would be updated constantly, as things change. This system could be built and launched in just a few years, if the money could be found.

12

these people are unreasonable and unrealistic.

what you want is as close to literally impossible as you can get. The simple fact that we’ve evolved into what we are and thrived is due solely to what this planet does to protect life. “Space” isn’t empty. there’s a ton of ionizing radiation out there (which our planet’s magnetic field and atmosphere shield us from,) no air to breathe, no food to eat. Everything we would need to sustain us in space would have to be taken from Earth.

at any rate, you’re worried about the wrong problem. Launching shit into space is (relatively speaking) piss easy. We’ve done it regularly since the late 1950s. The hard problem is keeping people alive in space long term. Being in space would be neat until you freeze, starve, asphyxiate, or get a novel form of cancer from the radiation.

and besides, your opening post shows how poorly thought out your whole proposal is:

just getting started would mean we’d have to accelerate that resource extraction you seem to despise. We’d have to strip and trash this planet in order to build enough for more than an insignificant fraction of people to leave it.

no thanks.

I believe we aren’t that far from sending at least a few people to Mars (since it’s the outermost planet in the system we can land on) but it’s still going to be a while and I don’t see us going much further. Everything you’ll need in space, you’ll have to take with you. The longer you’re out there or the further you go, the more shit you need to bring.

13

Nowhere do I imply that significant portions of the world’s population are going to migrate off-planet. What I am implying is that the human race is consuming the resources of this planet at a rate which means that we are going have great difficulty meeting our needs in the near future. For example, the Deepwater Horizon was drilling a well in 5,000 feet of water when the blowout occurred. Why? Because all the easy oil is gone. Before the most recent decline in crude oil prices, serious effort was being made to drill in 10,000 feet of water, going three miles beneath the sea bed, in order to reach oil. We will never run out of oil, but it will become too expensive to use for fuel.

Copper is another example. Demand for copper is so great that mining a mountain in Alaska that is at the headwaters of the most productive salmon runs in the world is moving forward, with both underground and pit mining being considered. Take a look at Butte, Montana to find out where that leads. The Berkeley Pit is filling with water that is poisonous and caustic, with a ph of about 2.5.

Yes, we have to take some stuff with us when we leave Earth, but we eventually will be able to replicate most of conditions on Earth, so that we can grow food, produce oxygen, and feel weight. Learning to shield our vessels from radiation is a critical step in being able to get off-planet for any length of time, if we go beyond the van Allen belts. And all of the minerals that we can find on Earth are in space, often just floating around in big chunks called asteroids.

And one of the most vital resources, which is so scarce on Earth, is energy. In space, energy is so abundant that you have to learn to protect yourself from it. Any industrial process can be carried out in space, many of which are either impossible or very difficult on Earth. And accidents won’t threaten thousands of people. Remember Bhopal?

Launching stuff on rockets is pretty simple, as long as it doesn’t matter if a rocket blows up once in a while. But that is not acceptable when there are people riding the rocket, which is why it has been so long since the United States has had manned launch capability. Because everything has to work, period.

14

So a space catapult? Uh-huh. Give us some more details on how it’s supposed to work.
picks at something under fingernail

15

Yes, and in your drive to get off of it, you’ll accelerate that consumption of resources.

we’re already preparing for that future.

yeah, and to make the things you need to get off of this planet, you’ll need even more copper, which will incentivize companies to use even more destructive mining practices.

The universe works as dictated by physics, not plot devices thought up by science fiction writers.

you’re hand-waving away a lot of things which are difficult, expensive, or both. You can’t just stick your hand out of the window and grab an asteroid. you have to get there first, it took Dawn three years to reach Vesta in the asteroid belt. and that’s just a one-way trip.

how do you capture that energy and convert it into something useful?

we only retired the shuttle a few years ago.

16

No, not a ‘space catapult’, this is not an idea about throwing something into space from the surface of the planet. This is an idea about using a linear motor, or rail gun, to get a very large aircraft moving fast enough to reach take-off speed in a short distance, just like a catapult on an aircraft carrier. (Which, by the way, they are planning on using linear motors for instead of steam.)

Because human beings don’t seem to take very intense magnetic fields very well, and linear motors create very intense magnetic fields when starting a mass into motion, I suggest using a combination of winches and rockets to get the whole mess moving about 10 miles per hour, then cutting in the linear motor. The slug that the motor reacts with would be ahead of and beneath the cart that the aircraft-spacecraft stack ride upon, to minimize the exposure to the electromagnetic radiation. Coils surrounding the path of the slug are energized in sequence, slightly ahead of the slug, which pulls it forward.

As the velocity increases, the coils are energized at a faster rate. Electric motors can generate incredible amounts of torque, far more than internal combustion engines can. So accelerating several million pounds to 300 miles per hour will not take very long, less than a mile. This velocity insures that the wing is moving fast enough to generate sufficient lift to take off, and the cart supports the wing-spacecraft stack. This eliminates the need for a massive undercarriage on the wing, saving many tons of weight.

The catapult would be long enough that the stack can be slowed down and stopped if an abort is required, just like an airliner in a refused take-off situation. The track would be straight, and should be as close to sea level as possible, so that the maximum air density is available. By moving the stack so fast, wind direction becomes moot, as the take-off velocity will be exceeded by 50 miles per hour or more. The wing will have enough engines that it will be able to maintain its speed, and even increase it. Also, the wing would be secured to the cart until it generates enough lift to ensure a strong lift-off.

For the spacecraft, there would be nothing to do for the first hour or so after lift-off. The carrier wing would be doing all the work, lifting the spacecraft to altitude, while carrying it up-range from the take-off site, so that an abort to the launch site would be feasible. This is one of the reasons that I think cryogenic fuels would not be a good idea, as much would boil off in the hour or so that it takes to reach separation altitude.

17

jz78817

What I am hearing you saying is that the human race is doomed to destroy itself fighting over the finite resources of planet Earth. I believe that we can make a better future than that.

18

I said no such thing. I’m saying you’re talking a load of bollocks. first the notion that some portion of us will have to leave the planet in order to survive, secondly how consistently you hand-wave away all of the problems and challenges of keeping us meatsacks alive in space. you propose that it be done using technologies which don’t exist and aren’t likely to exist for a very long time, if ever. and further, you’ve already said it wouldn’t be “significant portions” of the population migrating off-planet. So who would go? The wealthy? just people who are “important?”

So do I, but I don’t think it will require leaving the planet.

with the technology we have today, and are likely to have in the near- to somewhat-distant future, even if the world descends into “Walking Dead” or “Terminator” chaos, it’d still be far, far more possible for people to survive down here than they could in space (long term.)

19

When an oil worker heads off to the drilling platform out in the ocean, he is not ‘leaving the planet’. What I am talking about is industry in space, utilizing resources found in space, to make things that we need on Earth. I am not talking about colonies, or people moving off-planet permanently, just spending a few months to a year or so working in space.

You are right, we do not have the technology to keep humans alive in space for long periods of time, but we can learn, just as the Inuit learned how to survive in polar regions. The day will come when we are importing finished metal pieces which can be assembled into automobiles, bicycles, and motors, or ceramics which can be used to build houses, refined metals like copper and platinum, and other products which no one can imagine right now, just as no one could imagine little old ladies napping while flying across the ocean at hundreds of miles per hour when the Wright brothers first proved heavier-than-air flight was possible. There were many people back then who saw absolutely no future in aircraft. I am glad that they were wrong.

There is do doubt that the resources of this planet are finite, while the population is growing. More and more people want a better standard of living, so demand for those resources is increasing. We are beginning to threaten our very survival with our desire to live comfortably. It does not have to be like that, when we know that there are huge quantities of stuff not far away.

If we had a Saturn 5 moon rocket in low Earth orbit, we could be at any one of the planets in a matter of weeks. Right now, we are trying to send stuff to distant planets using what are little more than model rocket engines. We have to play pool with the solar system to achieve the velocity needed to reach other planets, because we have to launch the entire spacecraft complete from Earth in one shot. When we can assemble them in orbit, fuel them up, and send them on their way, distances will seem much smaller.

There was a time when traveling from England to Australia would take over a year, and most people figured that they would never return when they left. Nowadays, you can make the flight in less than 24 hours. When going to Mars will take over a year, radiation exposure is a serious problem. But if we could make the trip in 3 or 4 weeks, the radiation is not so much of a problem. No one would have believed that a ship with no anchors could drill an oil well in 5000 feet of water 20 years ago, but it is commonplace today. We have no idea what we are capable of, but we do know that we will never find out if we don’t try.

20

One of the reasons why this is so important to me is that our existence on this planet is very precarious. The Solar System is still filled with junk left over from its formation, and every once in a while we run into some of it. Back in the early 1990’s, I noticed a short little blurb on the third or fourth page of the paper talking about an asteroid that had passed between the Earth and the Moon. No one knew that this asteroid was there until it was between the Earth and the Moon, and it was about 1 mile in diameter, which is what is estimated to be the size of the asteroid which is believed to have wiped out the dinosaurs.

The human race could have been obliterated without even knowing what hit us. We need to develop a different perspective on where we live, and realize that it is terribly fragile, and could be destroyed easily. And we must accept that human actions can effect the entire planet. The most effective way to to alter people’s perceptions about the Earth is have some people start working somewhere else, off planet. Either in orbit, or on the Moon, or on a probe to sample some asteroids. When we know that there are people living and working in space, people who are somewhere other than on Earth, it will begin to affect our thinking. The most powerful symbol of the finite nature of the Earth is the Earth’s moon, Luna, which is a visible place.

Many people refuse to believe that humans have landed on the Moon, because that implies that the Earth is not infinite, that it does not go on forever. If it does not go on forever, than what is outside of it? Thinking about that terrifies some people, while others have just never considered it. When you tell someone that the Sun is a star, there is a good chance that they will not believe you, or that they will be shocked, because they have never considered the idea of other places. If people are convinced that the Earth is infinite, than they will not hesitate to dump their waste into the water and the air.