BBC Focus Magazine

[Nike2020]

In most Sci-Fi films there are space ships... but
when you think about it if there were a journey to mars for example it would be simply a matter of setting co-ordinates and heading in one direction for weeks... in space it would be a smooth straight ride as if on a train track... this trainlike vehicle - not considering the propulsion system- would be self contained with air, water, food, accomodation, communication etc... this could even be tested before going into space... when I think about it this propably won't catch on in the movies

[M Paul Lloyd]

Real life space travel is never going to be quite as dramatic as it appears in fiction. A good example is the film '2001 A Space Odyssey' which is not quite the same as Star Wars or Star Trek but is actually far more accurate.

[Shadowwolf]

Well technically anything up there is a space ship but I take it you suggest a configuration of modular externally similar units connected together in a series akin to a train.

Could be I suppose, the ISS is a multi-module construct so it may follow a similar principle. But how would such a thing get down, would really have to act as an orbital station with the capability to launch an away mission. Actually that has me wondering, just what size craft would have it have to be so as to land and be able to leave again? It would need large engines and carry rather a lot of fuel so as to break Martian gravity which is a lot heavier than the Moons weak pull.

A good example is the film '2001 A Space Odyssey' which is not quite the same as Star Wars or Star Trek but is actually far more accurate.

Dammit I wanted a B'rel class Bird 'O' Prey!

[M Paul Lloyd]

A modular space vehicle is the most likely design to go with as each component could be lifted to orbit, assembled, fitted out and fueled in relative safety. The only real problem is the total mass of such a 'train' along with its propulsion system and of course its propellant, which is always a problem as the greater the mass of propellant the more propellant you need.
You could of course build a lot of small ships and join them together to form a 'train' configuration.

[Healerman]

There is also the possibility of a whirling "bolas" arrangement, capsules tethered together and spun up to provide "gravity". Highly practical given what space medicine is teaching us about the depredations of exposure to microgravity.

Dammit I wanted a B'rel class Bird 'O' Prey!

Nah! a D'Deridex warbird with all that cool glowing thing going on.

[Shadowwolf]

Okay it has an eerie glow and it's bigger I'll give you that but it's still a Bird of Prey for me, Klingons are more fun

[M Paul Lloyd]

Well I bagsy the Shadowwolf then.

[Nike2020]

[quote="Shadowwolf"]Well technically anything up there is a space ship but I take it you suggest a configuration of modular externally similar units connected together in a series akin to a train.

... Actually that has me wondering, just what size craft would have it have to be so as to land and be able to leave again? It would need large engines and carry rather a lot of fuel so as to break Martian gravity which is a lot heavier than the Moons weak pull.
quote]

Ok say it is possible with todays technology to have lots of cargo, similar to a freight train... the propulsion system would be the same in space for a small vehicle as a large vehicle (er am I right on this point mods?) then consider the discovery of fuel or oil on mars? a realistic proposition believe it or not! jackpot...plus no pollution on earth... just some angry martians lol

[Shadowwolf]

It might be the same engine but it would need to be larger providing greater thrust if we hoped to get anywhere fast. A small engine will only move a larger mass slowly, too small and it won't have any effect.

As for discovering a fuel source on Mars, whilst it may be likely it would not be the best idea to bank on finding it and have no other option. Which is why whatever goes down will probably need a dependable source of thrust to get back up.

[Colm]

Thing about Sci-Fi is that they always underestimate the size of space... Outer space is a huge, huge, huge place and it is virtually all nothingness. The chances of a spaceship going in a random direction just happening to pass by an anomoly or a wormhole (if such things exist) or whatever are extremely remote...

[M Paul Lloyd]

A paddle boat lost in the Pacific is less insignificant.

[dagncl]

I guess we'd be looking to use the ice on Mars as a fuel to get back (there's lots of hydrogen to be harvested!). How we'd extract and process it would be the next problem though.

In reality a Mars mission may involve a few craft being launched at various stages. That way we could get a lander in orbit first, perhaps even land some gear onto the surface in preparation for the manned mission.

[M Paul Lloyd]

Its not so much fuel that we need water for but as a propellant.

We could certainly split water into hydrogen and oyxgen to provide a really efficient burn from a convetional reaction jet thus creating a propulsive gas, but that would be very inefficient to produce, compress and indeed store for any period of time and for interplanetary travel it would make more sense to use a nuclear reactor to heat water and squirt it out of the back as steam.

Or as I prefer, save the water for human useage and use a propellant, such as Martian/Lunar dust, which could be used to impart thrust by ejecting it via an electromagnetic field.
Such devices exist and work really well but seem to get ignored for some reason?

[worldmaker]

In most Sci-Fi films there are space ships... but
... it would be simply a matter of setting co-ordinates and heading in one direction for weeks... in space it would be a smooth straight ride as if on a train track... when I think about it this propably won't catch on in the movies

The dynamics of space flight might not catch on, soooo slooooooow to get them but you can always edit out the boring 99.99995 of the journey.

The make it attractive to film and TV production entertainment you need an entertaining design, not just a bunch of plain capsules.

So a really pretty design, now let me see, hmmmmm, SpringShip!

[Colm]

Oh BTW... Just to be annoying... Space Plane - not possible, since space is a vacuum!

[M Paul Lloyd]

Oh BTW... Just to be annoying... Space Plane - not possible, since space is a vacuum!

True, although the proper definition of a Spaceplane is a space capable vehicle which can take off and land much like a coneventional aeroplane, a system that we have yet to fully achieve but the current development of the old Skylon project is starting to show some promise.

http://www.bbc.co.uk/news/science-environment-17864782