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the next 200 years of space exploration

Posted: Tue Oct 16, 2012 4:41 am
by roid
This was a great post spelling out the possible path the next 200 years of space exploration will take. Which will take us to the level where we as a species are spread over the solar system, with permanent settlement on the moon, mars, venus, the moons of Jupiter, the asteroid belt... and are approaching the viablity of sending off interstellar missions to other stars systems.
Seems like a pretty plausible schedule eh.

"Stephen Ashworth sits in at Centauri Dreams to riff on a big question: How are we going to build the Solar System-wide infrastructure we need to launch an eventual interstellar mission?"
http://www.centauri-dreams.org/?p=24996
A scenario for the ten-billion-times growth factor

Within this middle way scenario, I would envisage the following sequence of events for the future of manned spaceflight merging into Solar System colonisation.

1. Government exploration missions to low Earth orbit, and establishment of an outpost there. (Now complete.)

2. Based on the exploration in step 1, private enterprise now markets low Earth orbit for commercial passenger spaceflight, dominated by space tourism but also featuring commercial space manufacturing and university-funded science, and creates a growing, economically self-sustaining low Earth orbit infrastructure. (Now just beginning, and dependent upon SKYLON-type vehicles for full success. Expect this phase to unfold during the 2020s, with ultimately thousands of passengers flying to orbit and back every week.)

3. As low Earth orbit becomes more populated and costs of access fall, a market will appear for lunar flyby trips (Space Adventures has announced it already has one committed client for a flight around 2015). These are best satisfied by adapting existing space hotel designs for injection into Earth-Moon cycler orbits, thus ensuring that full solar flare protection, repair facilities and buffers of consumables can be built up in cislunar space. (Late 2020s to 2030s.)

4. The growing space hotel system and the demand for translunar propellants create a large-scale market for volatiles, especially water, in orbit which can be satisfied by robotic mining of the near-Earth asteroids; again, government exploration, in this case robotic asteroid exploration, will be needed to develop the technologies towards commercial sustainability. (2030s to 2040s.)

5. Based on the infrastructure in steps 2, 3 and 4, governments, singly or in collaboration, now launch new exploration missions to the Moon very much more economically than could have been achieved with an Apollo-style system, and establish one or more outposts there. (2050s.)

6. Based on the infrastructure in steps 2, 3 and 4, the construction of solar power satellites to serve Earth now becomes economically attractive, and the conversion of Earth from fossil fuels to solar power begins. (2030s to 2050s.)

7. Based on the exploration in step 5, private enterprise now markets the Moon for commercial passenger spaceflight, dominated by space tourism but also featuring lunar surface science, and creates a growing, economically self-sustaining lunar surface infrastructure. (2060s.)

8. Based on the infrastructure in steps 2, 3 and 4, government now launches exploration missions to Mars and Venus, and establishes outposts there. (2080s.)

9. Based on the exploration in step 8, private enterprise now markets Mars and Venus for commercial passenger spaceflight, dominated by science and colonisation. Interplanetary transport will use a network of cycler stations based on several decades of experience with Earth-Moon cycler stations. (Into the 2100s.)

10. Outposts on Mars and Venus grow into colonies, and meanwhile the cycler stations also grow into substantial transit cities, supplied from asteroids rather than from Earth. (First half of the 22nd century.)

11. Based on the existing interplanetary infrastructure, government now launches exploration missions to the Main Asteroid Belt, Jupiter and further afield. (Mid-22nd century.)

12. Based on the exploration in step 11 and several decades of experience operating interplanetary cycler stations, private enterprise sets up mining and construction ventures in the Main Asteroid Belt to create self-sufficient colonies there. New cycler stations link these colonies with the inner planets. (Mid-22nd century.)

13. At the same time, private enterprise sets up cycler stations to serve Jupiter and Saturn, serving growing colonies on the respective giant planets’ moons and among the Jupiter Trojan asteroids. (Late 22nd century.)

14. The interplanetary economy is now growing independently of Earth, but at the same time the commerce (material, energy, information) between the colonies and Earth enriches civilisation at all locations. (The state of play at 1 January 2200.)

This scenario thus completes the transformation of civilisation from monoplanetary to multiplanetary status, and sets up the conditions under which economic and population growth may now proceed without interruption until the limits of the carrying capacity of the Solar System are reached.

(cont...)

Re: the next 200 years of space exploration

Posted: Tue Oct 16, 2012 8:57 am
by snoopy
Very interesting. I'd love to see it happen.... to live in space at some point in my life. Well, maybe I'd actually prefer to live in the ocean at some point in my life... but either way exploration would be cool.

A few interesting implications:

1. If things really progress according to this timeline, I'd potentially live to see self-sustaining life on the moon. That would be so cool.
2. Until we figure out how to travel faster than light, this will eventually create a new barrier to an individual's experience. Right now, anyone can literally get anywhere within an extremely small portion of their lifespan. As we get more spread out, it's going to take larger and larger time investments to travel to the extents of civilization. This will especially show itself when we start to try to go inter-stellar... it'll take generations to get there... we'll have to have high quality mechanisms to preserve memory, information, and discipline over generations of time.


P.S. I'm also skeptical. I think we under estimate the awesome wealth of resources that the earth is compared to space/asteroids/the moon. Like I said, I'd love to see it happen, but the pessimist in me doubts we'll ever colonize anywhere off of this planet.

Re: the next 200 years of space exploration

Posted: Tue Oct 16, 2012 6:03 pm
by roid
EVER?
D:

but ... but ... but technology is ever marching forward in sophistication and miniaturisation. If it continues as it has been - we'll inevitably have devices smaller than can be seen with the naked eye which are capable of feats we only theorise about currently.

I mean, given the current pace of technological progress over the past 100 years alone (hell, look at the last 20 years of information tech), think of what things will be like in 10,000 years. You'll either be able to press a button on your suit and it'll puke out an airtight moon-building, or you'll just be genetically re-engineered to be able to survive quite well naked in space.

EVER?

Re: the next 200 years of space exploration

Posted: Tue Oct 16, 2012 6:18 pm
by Isaac
Once we make it really cheep to shoot stuff into space (rail gun?) we're going to have more drones in space than people on Earth.

Re: the next 200 years of space exploration

Posted: Tue Oct 16, 2012 6:33 pm
by roid
Isaac wrote:cheep to shoot stuff into space
Image

Re: the next 200 years of space exploration

Posted: Tue Oct 16, 2012 6:48 pm
by Isaac
Angry Birds, the most accurate scifi game in predicting future space exploration.

Re: the next 200 years of space exploration

Posted: Wed Oct 17, 2012 10:31 pm
by Avder
I would love to live the last years of my life in a cloud city hovering in the outer atmosphere of Saturn.

Honestly I think there are two things that permanent colonization of bodies other than earth depends on:

1. How the human body reacts in fractional gravity (such as on the Moon, Mars, an Asteroid, and the moons of the Gas Giants) and

2. If we ever develop a device that can give artificial gravity without using kinetic motion (I.E. "gravity plating" and the like which enables a 1G environment on the Starship Enterprise).

If the human body can not be maintained in a fractional gravity environment without the physical activity regimen that people aboard the international space station, then environments like the Moon, Mars, asteroids and the like will not be suitable for general colonization because the general public is not going to want to commit to keeping themselves THAT fit just to be able to live somewhere unless they are a space die-hard. If that is the case, we will have to wait and see if gravity plating can be developed which would allow colonization on any rock in the solar system (and even places where no rock exists, such as lagrange points) since it could be used to simulate a 1G environment anywhere.

And if that's the case, that means Mars and the Moon get bumped way down on the list of human-habitable environments and a couple of other locations come way up: The atmospheres of Venus, Saturn, Uranus and Neptune. Why these places? They all have points where the gravity is near 1G, and all could potentially have floating cities built in them.

Saturn I think could be especially lucrative. The gas giants themselves are made mostly of hydrogen, which hopefully we will learn to fuse into helium for a net gain of energy. This would mean that any floating city on Saturn could be powered by the envrionment it floats in, and the energy generated could be used to heat the city to earth-like temperatures, run air scrubbers that filter and replenish the cities supply of oxygen, and so on. In addition, the moons of Saturn are extremely rich in resources that humans would need in order to live on Saturn. There are generous supplies of water, hydrocarbon fuels, and all kinds of other goodies readily available.

Plus the view would probably be spectacular.

Yeah man, Saturn. That's where it's at. The best day of the week is named after that planet for a reason.

Re: the next 200 years of space exploration

Posted: Wed Oct 17, 2012 11:00 pm
by Isaac
Well, I think at first, space will only be lived in by the most die hard space nuts. Kinda like those guys that live in the arctic. And gravity space plating shouldn't be necessary, since spinning your space station will produce gravity.

Women in space suits? Hot!

Image

Re: the next 200 years of space exploration

Posted: Thu Oct 18, 2012 8:38 pm
by Avder
A spinning space station needs to be absolutely huge in order to have the angular momentum needed to generate 1G of outward force that would simulate gravity. If we were to somehow find a way to invent gravity plating, we could have 1g environments in spaces as small as the International Space Station, the Space Shuttle, or hell even a flying Winnebago or whatever we throw out there. It would make the scale of construction vastly more manageable for small or medium sized space colonization firms and allow for smaller "space villages" instead of what would almost certainly be space metropolises on gigantic rotating stations.

Re: the next 200 years of space exploration

Posted: Thu Oct 18, 2012 9:08 pm
by Isaac
First off, you didn't say anything about the hot space chick.

Second, I've ridden on the gravitron ride, which isn't very big, and can turn upside down or sideways, as the gentleman does in the video. I assume if I were to send the gravitron into space I would only need to spin it a bit faster to get enough gravity to be comfortable.

Re: the next 200 years of space exploration

Posted: Thu Oct 18, 2012 9:20 pm
by Krom
Star Trek style artificial gravity is about as impossible as the transporter, mostly because when you think about it the gravity field didn't even extend beyond the hull of the ship where real gravity has a much MUCH longer reach.

One way you could theoretically fake gravity even in a small craft would be plain acceleration. You simply accelerate at a constant 1G till you are halfway to your destination, then you turn around and decelerate at 1G for the rest of the trip. Since the solar system is so big, it'd be perfect for traveling between planets and such, since the distances are so great even with that kind of acceleration it'd still take a long time to get anywhere. It would require a incredibly efficient and powerful engine to pull off and would be useless for space stations and the like, but it'd pretty much perfectly simulate gravity on a spaceship.

Another thing I think would probably have to be addressed if people were traveling about the solar system all the time would be how exactly do you protect them from micro meteors and other debris in space. While the odds of any astronaut today getting hit by meteors or space debris are "astronomically" low, if thousands or millions of people were traveling through the solar system everyday collisions would definitely happen. I wouldn't want to be the first person to find out what happens when you hit a bunch of meteor debris the consistency of sand at 10+ kilometers per second relative velocity...

Re: the next 200 years of space exploration

Posted: Thu Oct 18, 2012 9:34 pm
by Spidey
Artificial gravity will be possible as soon as we figure out how to bend space. But since we don’t even know what space is, or how matter bends it, I would imagine it’s still pretty far off.

Re: the next 200 years of space exploration

Posted: Fri Oct 19, 2012 5:31 am
by roid
yeah if we can create artificial gravity then all bets are off, coz it's also the real theoretical basis for warp drives that can travel faster than light. If we had gravity manipulation, then not only will our gravitational comfort be the last thing on our minds, but the physical time constraints limiting our travel outof our solar system will also no longer be a big issue. The goalposts will have instantly moved a lot closer, OP's plan will be significantly shortened (if not made outright redundant!). Best leave notions of gravity manipulation to the realms of Science-FICTION for the time being.

OP is more a plan of how the economics of the near-future progress of space exploration will pan out. But if economics wasn't a factor, there's very little technology-wise in the plan that we couldn't already do right now. The robotic & space-based mining on planets and asteroids from step 2 (2030s to 2040s) and step 12 (Mid-22nd century) are the major questions IMO, breaking quite new ground there - not sure what kinds of roadblocks it'll throw up.
Everything in the list is slowed by the need to wait for the slow growth of the respective supporting economies (and growths in population and generational education constraints) they will be enabling. However if money, materials and manpower wasn't an issue you could get the entire list done within only a couple of years IMHO, 10 years max. There's nothing too fanciful in there from a technology point of view, the vast majority of it are merely larger versions of currently existing tech. It's just expensive is all, so it needs to be a part of a larger economy to support and utilise it. It takes time for economies and cultures to change and adapt to such things.

Typical example: SpaceX recently leaked that it was working on a design for a 200-tons-to-orbit launch system, it's by far the biggest ever. It's to be assumed that there is no satellite yet in existence heavy enough to utilise this capability, since the capability to launch such a weight has never existed. So SpaceX will likely have to wait a while for it's first customer on that launch system, payoffs for pushing the limits are very slow to materialise when you have to wait for a whole supporting economy to catch up to you.

Re: the next 200 years of space exploration

Posted: Fri Oct 19, 2012 4:58 pm
by Avder
I thought the current real basis for theoretical warp drive was either ultra-magnets, or utilizing negative energy?

But yes, I realize there is almost no real life basis for star-trek like artificial gravity at this point, but our understanding of how gravity works is extremely limited compared to anything electro-magnetic related.

Re: the next 200 years of space exploration

Posted: Sat Oct 20, 2012 10:51 pm
by roid
(omfg, i just accidentally hit refresh and lost my huge post just before i submitted it. GARHASRLKHSF. rewrite)

yeah you're right, you'll likely need negative energy/mass too to form a complete warp bubble, so your arse isn't hanging out the back.
On rethink, i'm not entirely sure if you can go faster than light with just the ability to manipulate "positive" (vanilla) mass. We know that the force of gravity alone is quite sufficient to reach C speed, eg: event horizons around black holes. It there is something behind an event horizon, then the gravity drive (i don't know what else to call it) would be able to find out. Since it'd be able to go fast enough to create (and then subsequently de-accelerate outof) it's own event horizon. (You may be spagettified, i dunno, YOLO)

Hang a "gravity plate" on a telescopic pole, extending out from infront of a space-ship. Like a carrot on a stick infront of a donkey.
- Turn the plate on, it becomes super-heavy, and the ship gravitates towards it.
- (Let the pole "telescope" up all on it's own, shortening as the ship falls towards the plate)
- Turn the plate off, it now weighs practically nothing.
- Extend the pole back out again, it takes almost no energy since the plate is so light when it's turned off.
- (The ship and plate are now drifting forwards in space, having expended no mass and very little energy)
- Repeat (turn the plate back on again).

You could keep accelerating forever. It's like a planet you can fall towards forever but never crash into, you just keep falling faster and faster and faster. As soon as you get close to the planet, you click your fingers and the planet teleports (energy free) further ahead of you.

It's been a while since i've thought about this relativistic stuff, I'm still not back in the mindset, i've probably got a whole lot of stuff wrong here. Particularly the notion that a sufficiently fast ship will create it's own event horizon, on rethink i can't remember exactly why i wrote that *shrug*, i can't subsequently think of why it would be right OR wrong. Bluh.

Re: the next 200 years of space exploration

Posted: Sun Oct 21, 2012 1:56 am
by sdfgeoff
Ever read any of Alan Dean Foster's commenwealth books?

They use the 'KK' drive, which is almost exactly what you describe, but they generate a mass 'field' in front of the ship, rather than just increase the mass of something. There's a complete description of this over here. This can also be used as a weapon, as it will attract towards other mass (= homing. Especially to other vessel drives) and anything within the field get's torn apart by the gravity gradient (not to mention the thermonuclear warhead they fitted to the front of the weaponized version).

They also have one object within the universe that uses cosmic movement vs the objects inertia for it's power source. It will stay still in relative space, but anything else in the universe moving powers it. The main character in tries to move this object, and by doing so moves the universe around it. This guy just spouts ideas.


One way you could theoretically fake gravity even in a small craft would be plain acceleration.... but it'd pretty much perfectly simulate gravity on a spaceship.
Isn't this exactly what Einstien based his theory of relativity on? That you cannot tell the difference between acceleration and gravity?

Re: the next 200 years of space exploration

Posted: Sun Oct 21, 2012 11:03 am
by Krom
Topic has been split: Keep religion out of our science fiction thread please.

Re: the next 200 years of space exploration

Posted: Mon Oct 22, 2012 9:44 am
by snoopy
roid wrote:EVER?
D:
...
EVER?
I guess it's a "glass half empty" vs. a "glass half full" thing.

A few things that make me skeptical:

1. It seems like the human race has a proclivity toward wasting inordinate amounts of productivity on entertainment. I just wonder if too many resources will be wasted on movies, iphones, and ipads for space travel to ever get to the point of being accessible to civilians. I.E. I don't think there's enough entertainment value in it to garner the masses support.

2. I think that the ease of life here on the earth is incredibly easy to under estimate. Compared to the logistics of supplying life in space, keeping people fed & comfortable here on earth is nothing... and we're still doing a poor job of it on the global scale.

3. I think that the value of resources to be had on asteriods/planets/etc. is being over-estimated. In the long run, I think it'll take so much productivity to get so little out of other celestial bodies that society will just reach a population plateau instead of mass-colonizing space. I.E. I think space life (while it may exist) may permanently remain a novelty.

4. I don't think we can maintain the level of technological advancement that's been the norm for the last century. We're starting to get to a point where we're at the limits of what Newtonian/Einstein physics can give us. Chips can't get smaller because of wavelengths and the size of atoms, bandwidths can't get wider because of the properties of light & electromagnetic waves, etc. Until we hit a real breakthrough in quantum computing, quantum/gravitational means of transport, and energy generation, I think we're getting very close to hitting a wall. I'm skeptical about the theories and lab experiments that are out there translating into financially accessible technology. Maybe the way to put it is this: I think the last century has been built on knowledge that fundamentally existed prior to that, and all we've done is perfected our application of the knowledge... to the point that we're approaching the limits of what can be done with that knowledge. I think the next set of knowledge isn't there yet... and that there are significant knowledge gaps (possibly due to physics just not operating the way we need it to) that are going to take too much time to and money to solve (if it's possible at all) for it to happen before something collapses and we have a technological back-slide.

I'd love to be wrong... I just tend to be a skeptic.

Re: the next 200 years of space exploration

Posted: Mon Oct 22, 2012 11:30 am
by Krom
Most of the problems you are talking about are basically energy problems, humans need energy to do pretty much anything. So the biggest issue is really just the energy issue, you need it for life support, food, water, propulsion, protection from solar radiation, communication, etc. Everything takes energy, the difference here on the ground is that the earth and sun supply a tremendous amount of that energy for us without us even having to lift a finger, but in space you only get what you take with you and what you can pull from the sun. Once we get our energy supply portable and economical enough that we can carry enough of it around with us to reach the other planets, then it will all fall in place naturally.

Re: the next 200 years of space exploration

Posted: Mon Oct 22, 2012 11:56 am
by Isaac
Say what you want, snoopy, on computer processing advancement. We are at an infancy level when it comes to our understanding of human physiology and its blending with technology. Our advancements there will minimize our life support expenses, with the goal of eliminating the expense altogether.

Re: the next 200 years of space exploration

Posted: Mon Oct 22, 2012 9:02 pm
by roid
One way of categorising the progress of human technology/civilisation is by energy source. To simmer it down: There's only so much power a human has in her own hands, and augmenting that with power from an outside source increases the human's productivity and capability.
- We were reliant on solar power for a while, heating things directly in the sun. Our methods of storing it were relatively short too: Wood is stored solar power from a few years to a few decades of growth. Our Horses and Bovines ate grass or grain, which was stored solar energy from only one season. The extra energy of wood and domestic animals allowed us to heat things to tremendous temperatures (relatively), and mass tilling of fields and increased transportation speeds/throughput (horseback or horse-drawn carriage).
- Or even better: COAL, an even more energy dense solar battery (these ones were charged millions of years ago). Technology went like the clappers with Coal (in good steam engines) with the industrial revolution. Unfortunately making coal is very inefficient (...the losses, omg the losses), and we use it way faster than it is created.

Some notes i typed up a few months back: "Using muscle power 1 hard working human can produce about 1kWh of work per day, and they will be paid maybe $80 for this http://www.youtube.com/watch?v=_CSMLyu4gf4 Petrol is 800 times as KWh/$ efficient as this."
... ok i have forgotten why i'm typing this. Moving on.

One way of extending solar power's (or any power source really) range is with power beaming lasers.
If a far away spacecraft flies a predictable path (pretty common) then focused power can be beamed directly at them from another location, via laser, to be picked up by solar panels.
Yet another example of the adage: Any transportation technology can be used as a weapon, and vice versa.

Also nuclear energy can supply all the portable power you need anyway, incredibly energy dense. If a spacecraft's weight is mostly nuclear fuel... well it's exciting to think of the possibilities. In either a slow burn for super long trips (super, like, woa, super long), or fast burn (what CAN'T you do with a few gigawatts of energy at your disposal? Lets fire plasma bolts at things, lets melt some asteroids, lets ride on streams of ionised atmosphere to land on planets and take off again).

But anyway, we're getting ahead of ourselves, most of this stuff i'm talking about is useful for interstellar travel. We don't really even need any of that to colonise the solar system, where solar power will still be readily available long after even the Earth itself is gone! Or until we become a Kardashev 2 civilisation and have the Sun surrounded with a dyson sphere or something. But yeah i can see power beaming comming into play in the more recent future, to boost the "solar" energy available to far out outposts (like, from Jupiter through to the Oort cloud).
We'll always have solar and nuclear in space, they're solid. All of our looming energy troubles are political in nature, don't mistake it for actual physical constraints or technological lackings. For instance, we have enough uranium alone to last thousands of years at least iirc, and that's not even including other fissiles like thorium.
And even if you wanted to stay on earth, we can have solar farms in space beaming energy back to earth. ie: limitless solar acreage.
I suppose we'll eventually reach a limit of expendable energy on the planet though, purely from radiated "heat islands" joining hands and inevitably effecting the whole climate. An analogy would be that ever since we've begun to utilise long-ago stored energy sources - we've been gradually strengthing a magnifying lens over the Earth, and since there's positive feedback loops in our climate (ie: water vapour) this increased heating will eventually become a problem. Solar-farms fit into this metaphor very well, since they are basically like mirrors, reflecting extra energy into the Earth that would have otherwise just passed us by.
There's only so much energy you can put into any physical system before it melts, hehe :D
(i'm not mentioning this coz i'm scared, but coz i think it's awesome that we'll eventually be so powerful that this will actually become a problem we'll have to manage. Kinda like airbags in cars, they weren't really needed until cars went fast enough to hurt the drivers, so their introduction is kinda like a "Wow, cars sure are getting really powerful!" award. As we become more powerful we take more steps to protect our squishy meat bodies from our own increasing capabilities. It's like our muscles are so powerful we're now at risk of breaking out own arms when we flex haha. Maybe we should redesign our bones too, to keep up ;))


hehe:
Although only several parts per million average concentration in coal before combustion (albeit more concentrated in ash), the theoretical maximum energy potential of trace uranium and thorium in coal (in breeder reactors) actually exceeds the energy released by burning the coal itself

Re: the next 200 years of space exploration

Posted: Mon Oct 22, 2012 9:38 pm
by Isaac
Combine that with being able to put your brain in a machine. I'd be posting messages here in REM sleep while riding a space laser, roid was ranting about.

Re: the next 200 years of space exploration

Posted: Mon Oct 22, 2012 9:49 pm
by Krom
roid wrote:Although only several parts per million average concentration in coal before combustion (albeit more concentrated in ash), the theoretical maximum energy potential of trace uranium and thorium in coal (in breeder reactors) actually exceeds the energy released by burning the coal itself
It shouldn't really be much of a surprise that a nuclear reaction is way more energy dense than a chemical reaction. :P

Although its funny you mention steam power as being in the past. Currently our most advanced power source: nuclear fission, is really just a heat source we use to boil water and create steam that spins a turbine. Coal plants do the same thing: boil water. We are STILL in the steam age. :P

Re: the next 200 years of space exploration

Posted: Mon Oct 22, 2012 9:51 pm
by Isaac
We run Thunderbunny on steam, still. Very efficient.

Re: the next 200 years of space exploration

Posted: Mon Oct 22, 2012 11:49 pm
by roid
Krom wrote:
roid wrote:Although only several parts per million average concentration in coal before combustion (albeit more concentrated in ash), the theoretical maximum energy potential of trace uranium and thorium in coal (in breeder reactors) actually exceeds the energy released by burning the coal itself
It shouldn't really be much of a surprise that a nuclear reaction is way more energy dense than a chemical reaction. :P

Although its funny you mention steam power as being in the past. Currently our most advanced power source: nuclear fission, is really just a heat source we use to boil water and create steam that spins a turbine. Coal plants do the same thing: boil water. We are STILL in the steam age. :P
heh, ya.
Just pressure increases from the phase change from water to gas.

hmm...
But we have internal combustion engines thesedays. They're not universal though, just cars and planes. Still a pressure change, but without a phase change, ICEs just expand AIR. They are hot air engines.
Since Coal and Nuclear still just use steam power, one would assume it's more efficient. i wonder would internal combustion engines in cars be more efficient if they were converted to external combustion engines (i don't mean Stirling engines) - ie: into steam cars? AFAIK the efficiency gains steam turbines have over ICEs are from the phase change from liquid to gas, you get more expansion from that phase change than you do from just thermally expanding a gas.

edit: seems the term to differentiate the 2 types of engine is "single phase" and "dual phase", depending if there's a phase change. haha wouldn't it be crazy to also use solid phase in there too for a triple phase engine, god damn. I've heard of solid/liquid phase engines that use wax and operate really slowly (they are used to adjust buoyancy on some AUVs (gliders), sometimes powered purely from the difference in ocean temp at various depths).
4 phase? i guess once you start working with plasma things get super weird, as you're no longer reliant on just pressure/temp to manipulate it.

Re: the next 200 years of space exploration

Posted: Tue Oct 23, 2012 8:59 am
by snoopy
roid wrote:Since Coal and Nuclear still just use steam power, one would assume it's more efficient. i wonder would internal combustion engines in cars be more efficient if they were converted to external combustion engines (i don't mean Stirling engines) - ie: into steam cars? AFAIK the efficiency gains steam turbines have over ICEs are from the phase change from liquid to gas, you get more expansion from that phase change than you do from just thermally expanding a gas.
I think it comes down to two things: the economics of scale and the responsiveness of the power production. I believe that ICE's scale down better than turbines economically, because a closed-loop turbine system has a higher baseline complexity/cost than engines. Also, internal combustion turbines aren't all that responsive... and closed loop turbine systems are worse - which means that you have to move to a stored energy model, which then further bumps up the baseline complexity.

That's why the research for better cars is really about coming up with better energy storage systems. If you can come up with a dense, efficient, safe method for storing electrical energy you can let the big power plants do your energy production at the efficiency that comes with scale, and all you have to do is store it until you need it to drive your car around. This is why gasoline is still king of the roost... because it's energy density is great and it's easy to transfer/transport.

Re: the next 200 years of space exploration

Posted: Wed Oct 24, 2012 3:14 pm
by Mobius
These predictions are pretty much 100% bull★■◆●, sorry people.

Firstly, making predictions like this, to 200 years in the future is 100% pure bull★■◆●, but the predictor has made some very fundamental mistakes which allow us to completely discount everything he or she says.

Why can't we predict even in the future? Because we have no idea what technologies are coming more than 10 years down the track. Imagine asking a person in London, in 1900 what the biggest problem facing Londoners in the year 2000 would be. Even the finest minds of the day, would reply that obtaining 8 million horses for the residents, and getting rid of tens of thousands of tons of horse ★■◆● each day would be almost impossible.

10 years later that future was completely changed by the invention of the motor car.

In a similar way, it is utterly stupid to attempt to predict the future. This is where the global warming doom sayers are retarded.

Announcing colonies on Venus is the most stupid thing I have heard in years. With a surface temperature of well over 450 degrees C, and with atmospheric pressure at over 90 atmospheres, it would be like trying to operate something at the bottom of the ocean, 900 metres down, in a bath of pure heat. It will NEVER happen.

Humans may one day land on Venus, but they'll be there for a couple of hours only, and it will probably be one of the most dangerous space missions ever undertaken.

Then there is the complete stupidity of space solar power. No idea in space history is more stupid than this. The numbers do not add up, nor can they ever be made to add up. Not even if you can get launch costs down to $10 a kilo. People who talk about space solar power beamed back to Earth simply have not made any investigations into the subject, and do not understand the issues.

Besides, Fusion power via LENR, Focus Fusion or Polywell Inertial Confinement will make all sources of power redundant within 15 years from now.

There's no mention at all of Beamed Power Launching, nor of a space elevator, both of which will contribute greatly to the occupation of space. It is unavoidable these two approaches will be used, because they offer the lowest cost to orbit of any possible method. Physics defines the lowest cost to orbit, and both these methods achieve that rate.

The list also completely excludes the transition of humanity to a Type I civilisation, on the Kardashev scale. This will mean humans control the same amount of energy as falls on the Earth from the sun: so,1.3 Kilowatts times the number of square metres which catch the sun's rays. Currently we are about 10% of the way there, but the other 90% will come in the next 50-80 years most likely. This ignores the existing rate of power increase, as once again, future technology drastically shortens the time taken to reach these power levels.

Once humans become a Type I civilisation, we will control the weather, prevent any nasty asteroids colliding with Earth.

It seems highly likely that Fusion Rockets will be available prior to fusion power stations, and efficient Fusion rockets will require only reaction mass to throw, which will most likely be fired from the surface of the moon using mass-drivers, and collected in orbit around the moon, before trucking to LEO.

As to artificial gravity, it's my belief that we will tame the gravity beast, but not for a long time, and when we do, a single AA cell battery will hover your car for half a year or so. Gravity is incredibly weak, and overcoming it will require technology, not massive power.

However, until that time, humans will be exposed to low gravity environments and be forced to live in rotating ships and stations. BUT, far more likely is that ships will maintain 10-20% of normal gravity for ease of operations, while the bad effects of zero G are completely mitigated by medical breakthroughs which prevent muscle wasting and calcium loss from bones.

There is more than one way to skin a cat.

But don't for a second think my predictions are much better than the first ones here - but mine ARE more accurate. And by "more accurate" what is mean is "less wrong". :P

Re: the next 200 years of space exploration

Posted: Wed Oct 24, 2012 3:30 pm
by Alter-Fox
But if no one ever tried to predict the future we'd be much deeper in **** than we are right now. To take your example, global warming is only a problem if we don't do anything effective about it. If no one had predicted in the first place that it would cause massive problems with weather and **** up the planet, the planet would be in even worse shape right now than it actually is because no one would know to try and do anything about it.
If no one had figured out that aerosol sprays were going to destroy the ozone layer the ozone would be depleting far faster than it is today and the world might already be uninhabitable for humans and other un-furred un-aquatic sorts of creatures.

Re: the next 200 years of space exploration

Posted: Wed Oct 24, 2012 5:39 pm
by Sergeant Thorne
Alter-Fox wrote:If no one had figured out that aerosol sprays were going to destroy the ozone layer the ozone would be depleting far faster than it is today and the world might already be uninhabitable for humans and other un-furred un-aquatic sorts of creatures.
Has nothing to do with predicting the future, and everything to do with perceiving and addressing a threat. That's like calling dealing with a hole in the hull of a ship "predicting the future", just because you understand exactly how it will effect the ship.
Mobius wrote:Once humans become a Type I civilisation, we will control the weather, prevent any nasty asteroids colliding with Earth.
I've heard that the configuration of our galaxy protects the Earth from nasty asteroids.

Once humans control the weather we will be well and truly screwed. ;) Actually I don't believe the weather is so controllable, and any control that will be exertable will only cause it to be unnaturally out of balance until that control is taken away. No? That's all weather is--the various elements of our planet attempting in a way to balance while shifting temperatures from the presence, absence, and position of the sun continually throws it out of balance, or, perhaps more accurately, changes the balance point (and all of this is very beneficial for life on earth, mostly).

Re: the next 200 years of space exploration

Posted: Wed Oct 24, 2012 5:53 pm
by Spidey
Sergeant Thorne wrote: I've heard that the configuration of our galaxy protects the Earth from nasty asteroids.
Where the heck did you hear that nonsense?

The closest thing I have heard to that is how Jupiter sucks up plenty of rocks.

Re: the next 200 years of space exploration

Posted: Wed Oct 24, 2012 5:58 pm
by Krom
Probably for every rock that Jupiter sucks up, it disrupts the orbit of another one and sends it chaotically flying about the solar system.

Re: the next 200 years of space exploration

Posted: Wed Oct 24, 2012 6:56 pm
by Alter-Fox
Sergeant Thorne wrote:
Alter-Fox wrote:If no one had figured out that aerosol sprays were going to destroy the ozone layer the ozone would be depleting far faster than it is today and the world might already be uninhabitable for humans and other un-furred un-aquatic sorts of creatures.
Has nothing to do with predicting the future, and everything to do with perceiving and addressing a threat. That's like calling dealing with a hole in the hull of a ship "predicting the future", just because you understand exactly how it will effect the ship.
I wasn't talking about threats we understand, like a hole in a ship. I was pointing out that if we never bothered to understand a threat we couldn't start to address it in the first place. That makes predictions relevant when exacerbating the threat enough to percieve it directly would cause a huge risk to all humanity and everything else alive on this planet.
In other words it has nothing to do with addressing a threat, and it's all about how we go about percieving it in the first place.

And if I didn't suck so much at making an argument I would have made that clearer the first time round. :lol:

Re: the next 200 years of space exploration

Posted: Sat Oct 27, 2012 6:54 am
by roid
Mobius wrote: space elevator
pfff, you have GOT to be kidding me. Talk about pie in the sky!

and "LENR, Focus Fusion or Polywell Inertial Confinement" are all yet to show energy gains afaik.

Hey we're all hopeful, but the ★■◆● in the OP are not pie in the sky technologies (well... space based mining is till yet to even remotely prove itself). It's mostly attainable right now. Yeah sure, new developments will change everything, change the timetable, they always do, but betting on the success of some new-fangled unproven technology (as you are) is more ridiculous than betting on the continued existance of the same (or better, which i guess is vaguely your point, and not so crazy TBH) success of specific EXISTING technologies. Best to just bet on the outcome eh? Space here we come, sooner or later.

New technologies will likely do nothing but INCREASE the timetable to space colonisation. The point of OP is that it's possible with our tech NOW... So if it's possible now, it can only get better with any new successful unpredicted techs.
So burn on, my prince Mobius.
Mobius wrote:...transition of humanity to a Type I civilisation
TBH do you really think we'll wait until we harvest 100% of the power of our planet before we blast off? Not bloody likely. Parallel development baby.
I meet ppl like this all the time, ppl who say "oh we should wait until we solve the PROBLEM X before we leave the planet". Problem X being whatever their short-sighted pet project is: animal welfare, social justice, international relations, global theocracy (OMFG). Pff, they put all their eggs in one basket, forget that they are not the only one with dreams & goals on this planet. Move over futurists, we ALL have own self-actualisation itching to blast off in any way possible :D. hehehehe
Mobius wrote:a single AA cell battery will hover your car for half a year or so
Wow that takes me back. How long have we been on this forum mate? haha. I can remember those exact words from you from my early days, the nTrap days probably. <3
But don't for a second think my predictions are much better than the first ones here - but mine ARE more accurate. And by "more accurate" what is mean is "less wrong".
hehehe. You and me, arbitrary future predictions at dawn (on planet/orbital/ringworld/dysonsphere/VRreality of choice). Choose your second ;P

Re: the next 200 years of space exploration

Posted: Sat Oct 27, 2012 7:09 am
by roid
Spidey wrote:
Sergeant Thorne wrote: I've heard that the configuration of our galaxy protects the Earth from nasty asteroids.
Where the heck did you hear that nonsense?

The closest thing I have heard to that is how Jupiter sucks up plenty of rocks.
yeah, he's probably* talking about Jupiter.
*(whether he realises it or not)

It seems to be part of our criteria atm while we look for extra-solar LIFE SUSTAINING planets - we look for systems that have at least one Jupiter sized gas giant. To suck up those pesky mass-extinction-causing comets.
Krom wrote:Probably for every rock that Jupiter sucks up, it disrupts the orbit of another one and sends it chaotically flying about the solar system.
Yep, it destabilises the orbits, and sends them to their makers (Sun, a gas giant, whatever) asap, instead of leaving them to take regular pot-shots at the planets for aeons after. So relatively older systems (like ours) end up safer, once they've passed their puberty (which i guess... ours has? lol idk).
Dinosaurs... goodnight sweet princes. But hey the survivors made for FABULOUS birds did they not? :E

Re: the next 200 years of space exploration

Posted: Sat Oct 27, 2012 10:03 am
by Alter-Fox
But if the dinosaurs never went extinct... what would we be right now?