You need to actually consider how expensive it is to carry materials into space.
And then. How to sustain life with those materials.

It's not like the world is just going to pool their money to do something awesome.

Food can be grown in space or on another planet, energy can be gathered in space or on another planet, water can be gathered on another planet. It's a matter of setting everything up.

If it becomes self sustainable- sure.

Interesting. You're saying we have a material that is heat-resistant, and one that is meteorite resistant, but no material which is both. Do you have a source for this?

http://en.wikipedia.org/wiki/Thermal_protection_tiles#High-temperature_reusable_surface_insulation_.28HRSI.29
You know it's reliable.
And yeah. Metal alloys can withstand micrometeorites- depending on strength. Otherwise we wouldn't have operable outer system probes.
Oh yeah, and theres another reason why you cant use meal for re-entry. Those materials are heat resistant. They keep heat from coming 'inside' the ship, therefore not frying the crew into human barbeque.
On the other hand, even if you found a metal alloy that didnt burn up while re-entering atmosphere, metals are generally- no all of them are (due to the fact that the very definition of metal, makes them heat conductive) heat conductive. And they will probably turn 'them' grilling nice for you to eat.

Some sort of ceramic composite armour on the outside of the vehicle might do the job, though it would have to reflect the heat as well as not burn up.

Failing that there has to be some method of slow reentry... but I have no idea how this could be done. I suppose they could minimise the speed of descent by applying thrust in the opposite direction, but I don't know if that would work. If it did it would take a long time I imagine.

Edit: http://arxiv.org/ftp/physics/papers/0701/0701094.pdf

It seems some research is being done into the development of carbon fibre parachutes to act as a reentry brake, cutting the speed to an eighth.

Okay, I suppose I was being unfair, then. However, it also mentions 'The only known technology in the early 1970's', so I think there could easily have been a breakthrough of sorts in that area.

1. Actually you were quite ignoring your common knowledge of the elements. This is what we learn in our school- US included. Lets put the fact together.
Heat resistance is due to the material's lack of free electrons, which are responsible for transmitting heat and electricity. It is they that define a 'metal'- which gives a metal the tint, strength (free electrons are attracted to protons of other particles, which bind and give them more durability and strength.), and most its characteristics.
But to have a material which has both heat resistance and strength would require them to 'not have' alot of free electrons- but has to compensate with more mass to give it more strength (more molecular mass means more attraction for each molecule, giving the material more strength. refer to gravitation.) But then to put a greater mass up in space and to attempt a reentry? I am sorry but that just doesn't work like that. (refer to gravitation again) More force would be required to slow down the craft. Now these complications makes breakthroughs easy.
2. You've read it wrong. It also says 'also', which means it is fragile currently also.

Anyone thought of putting metal... on top... of heat resistent material? Like an outer shell, so to speak, that still won't cook the crew.

Then uh, when the metals melt and you have to cut the hull to get the crew out- would you still consider that? Since one of the main purposes of a shuttle is to be reusable.

You can use metal that won't melt during re-entry, there are plenty of alloys that won't cook themselves up badly, especially if they're in contact with ceramic heat sinks like they have on shuttles.

I think the carbon fibre parachute idea is a good one for re-entry.

I'll summarise the salient points of the article (or you could just read the abstract).

1. A carbon fibre parachute weighing 226kg could exert a braking force of 1800kN on the descending spacecraft.
2. The friction caused by drag would heat the parachute to 1000-1300C; carbon fibre retains its useful properties up to 1500-2000C.
3. The parachute is so designed that heat dissipates from it very quickly.

Then weight becomes a problem too. It isn't a viable option now, but it maybe possible in the future- when somethings like carbon fibre parachutes come in place, or when a viable slow re-entry method takes place. (Currently, having too much weight will make the deceleration of the spacecraft too hard to land safely. And no material can save the ship from an impact like that.) Plus spaceships require insulation.

Um, all of this is well and good, but have you guys considered communication on such a massive scale? How are you supposed to talk to those far off colonies? It'll take enormous amounts of time to send and recieve messages, not to mention enormous amounts of money, and we don't even have a reliable system for sending messages like that. What will we do, build a massive line of sattelites to each and every planet so they can speak to the people that sent them to colonize the planets confidentially (It'd be pretty easy to just intercept messages moving across those huge distances)?

Also, it takes enormous amounts of money to build spaceships. The more technology you add, the more expensive it's going to be, and I think we're a long way off from making any of this efficient.

Is it really profitable to send these ships back and forth? I mean, to get those resources means sending the ships, but those ships need to be massive, bigger than anything we have right now, to give us anything in the way of the resources we need, and they'd have to be coming at regular intervals during the year, not just once every 5 or so.

Sorry if some of that wasn't quite understandable, it's pretty early here.

Edit: Once they become self sustaining, why would they give us their hard earned resources?

They wouldn't. Then there will be a war in all likelyhood.
Except isn't the point more so that they can sustain themselves, than make us profit?

Brilliant. Then again, you already answered this...
Additionally, there are other work arounds, such as having a ship which changes from meteriorite-resistant to heat-resistant by putting one plate of one above one of another as the need arises. When you're going back into the atmosphere, for instance. Will it make it heavier? Yes. However, the heat-resistant plates don't weigh that much.

Sure. Build satellites, and encode the messages.

Yes. When it becomes an option, different companies will start innovating and coming up with nice new technologies for really big spaceships. It should happen eventually. It'll be hard, but if its profitable, it's possible.

Because they're employees of company X, because they're self-sustaining in food and all but we provide luxuries like computers, and because we'll kick their ass if they don't.

Yeah, but you're forgetting that the farther out you go, the more time it takes to send messages back and forth, and also how long it takes to send ships back and forth. Once you reach a certain distance, those colonies will live entire generations before you can send them your luxuries, and after a few generations have come and gone, who would be left to care about corporate loyalty? Also, when a message takes a full light year (And probably more than that, if you expand past our solar system), how can that be feasible in any way shape or form? It'd be like Britians world wide colonies all over again, but it would take even longer to send messages back and forth.

As for the sattellites, what do you propose? That we just build a big old line of them out to wherever the colony is, over those huge distances? Keep in mind you still have to pay for the absolutely gargantuan ships and make those planets acceptable places to live, not to mention all the logistics on earth, the loading and unloading of materials, and all sorts of other things that you'd have to pay enormous amounts of money for.

Also, lol, no corporation has enough money to do tthese things, I don't think most national governments have anywhere near enough money to keep up such a program and make it profitable. You'd probably bankrupt yourself before you even got your first spaceship out. (Where the hell would they get that kind of power in the first place?)

Mars is the likeliest candidate to be colonized, not the moon. Aside from space colonization, we could construct an underwater city, cities and streets made on the very high levels of skyscrapers, underground cities, cities floating on top of the ocean, weatherizing inhabitable areas on Earth to make it "habitable", and so on. But then, they would be excessively expensive.

Moon has no atmosphere... or not even to sub-stain life that is.

Only means i see that the moon can be colonized is if the for the first few decades they set up "Eco Domes" until they can take the ice from Pluto and replenish the moons atmosphere. And the only way for the trip not to cost several million dollars, they should create a ship the uses a renewable resource since the main rocket of a space shuttle uses an extraordinarily amount of fuel mainly because its main design was actually based of the German weapon Ballistics V2 which was invented during the 40's... Anyhow i suggest that we create a ship uses the earths rotation (like a sling shot) using a super magnet thus reaching faster speed without the cost of gas.

Secondly once someone invents warp drive (reaching speed limit OR creating portal) it might become more cost effective).
As well as the fact of re-entry into the earths atmosphere has harmful radiation and small debris in the atmosphere (more noticeable on planets with larger asteroid belts)

I think that the easiest way to power a spaceship will be using nuclear energy. The USSR and probably the US experimented with nuclear reactors aboard planes (for indefinitely-flying nuclear bombers), but there wasn't a way to keep the radiation from hurting the pilots. On a significantly larger spaceship, fission technology can be used to great effect, and fusion, if sustainable, will be far better (fusion is an energy-gain reaction, as it converts some of the mass of two small atoms into pure energy. According to e=mc^2, that's a lot of energy). Especially if they figure out a way to miniaturize it. It's the one good way I see to power major spaceships to get to places fast. I believe modern craft that goes as far as pluto operates primarily on solar power - if we want to get to other systems, we need a reliable method of handling that distance. Now, all we need is a warp mode, and we'll pretty much have the technology to go anywhere.

Post has been edited 1 time(s), last time on Sep 7 2009, 12:37 am by Centreri.