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Space Train

A train that travels in a sraight line on a track built level against the curve of the Earth.
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Space Train is constructed of a seemingly endless series of cars that are unbending at their conjunctions, so that the train can only travel in a straight line. The track is electrically charged and the cars are powered like subway cars. The cars are very light, but very rigid, however the entire train is so long the overall mass is extremely great.

The train moves at an incredible rate of speed. The track is so long and straight that as the Earth curves the track must be elevated by support structures to keep it straight. The cars contain jet fuel and each car has jet propulsion. The support structure of the track is such a feat of engineering that the Earth appears shaped like a teardrop in two dimensional images from space.

The Space Train therefore has the first ever horizontal-vertical launch. Although the launch is technically horizontal it appears vertical depending where one is watching from on Earth. In fact two tracks intersecting at the point of the teardrop can launch Space Trains from two adjacent sides of the Earth.

rcarty, Feb 15 2013

Calculating distance to the horizon http://www.ringbell.co.uk/info/hdist.htm
Useful for this Idea; plug in 10000m height, see how long the straight track would be. [Vernon, Feb 16 2013]

[link]






       It's hard to know where to begin with this.
MaxwellBuchanan, Feb 15 2013
  

       You could start with some paragraph breaks. I want to like it, but it's going to take me a while to find a station to get on at.
normzone, Feb 15 2013
  

       Knowing nothing about space, I can only analyze the train- related aspects of this idea.
Alterother, Feb 15 2013
  

       The only flaws are the physics and engineering. It's inconceivable that this should not fail to work.
MaxwellBuchanan, Feb 15 2013
  

       // a track built level against the curve of the Earth // All the railways follow the Earth curvature at ground level . Why do this one need to reach space level ?
piluso, Feb 16 2013
  

       [MB] One day a train will be conducted straight into space and hats will be served in the dining car.   

       [Piluso] the track cannot follow the curvature of the Earth because the train must escape the pull of gravity and travel into space.   

       Based on the drawing I have made using a ruler and a compass, the train will not be travelling vertically and linearly from the centre of the Earth, but tangentally from the curve so the train given certain altitudinal loft will begin to descend orbitally towards the surface of the Earth. However, given enough escape velocity from accelerated mass and jet engines, Space Train will not descend into a catastrophic fiery wreck.
rcarty, Feb 16 2013
  

       Per the link and the calculator, a track 357.3 kilometers long, and perfectly straight, would have one end at the surface of the Earth and the other end 10,000 meters in the air. This is the altitude at which passenger jets routinely fly a little less than the speed of sound. That means you have all those kilometers to get your train up to that speed. Of course, if you want your train to go into orbit, you will need an even longer track.   

       The calculator says that for a 100 kilometer height, a conventional measure for "where the atmosphere ends and Space begins", the length of the perfectly straight track is 1133.9 kilometers. You will want your train to be traveling something like 29,000 kph to get into orbit, by the time it reaches the end of that track. Good luck!
Vernon, Feb 16 2013
  

       Knowing nothing about space, or trains..oh.   

       Suspect you could meaningfully turn that "going up into space" part of the track as a spiral, and try and re-use the energy from the coming-down train to help raise the going-up one.
not_morrison_rm, Feb 16 2013
  

       I suggest the whole thing can be easily powered by a cat-o-tron.   

       Briefly, the inner ring is a lined with buttered toast, butter outmost, and the outer ring has many cats strapped to it, feet innermost.
not_morrison_rm, Feb 16 2013
  

       When the Space Train is close for maintenance, will there be a Space Train Replacement Bus Service?
hippo, Feb 16 2013
  

       This idea is presented more of a thought experiment than a serious proposal. I'm trying to visualize what the experience would be for a passenger on the Space Train. The trip would undoubtedly start off horizontal, but given a track that remains level despite the curve of the Earth, would at one point passengers experience vertical ascent? My visualization is that it wouldn't, but given that from another point of observation on Earth the ascent would be vertical that conclusion might be incorrect.
rcarty, Feb 16 2013
  

       If the space train were circumnavigating the Earth really, really fast, like mathlessly fast, and the train remained pefectly 'level' (by which I'm assuming you mean 'upright'), logic dictates (to me) that at some point the passengers would experience weightlessness. It would be right about then that you'd fire off your lift rockets and the train would vector away from the planet, so it might be a good idea to have everyone remain seated, or to do a couple of zero-gravity playtime laps to let everyone get it out of their systems.
Alterother, Feb 16 2013
  

       My brain is melting.
Kansan101, Feb 16 2013
  

       Don't worry, that happens to everyone at some point. You know you've achieved critical mass when [beanangel] starts making sense.
Alterother, Feb 16 2013
  

       //mathlessly fast// [Marked-for-tagline]   

       There are three extreme options.   

       Option 1 - the track (and hence train) goes straight up (ie, the track is perpendicular to the Earth's surface). Unfeasible at present and, in any case, if you stepped off the train when it stopped at the top, you'd fall right back down again. Unless, that is, the track reached geostationary orbit, in which case you'd be weightless at the top and in geostationary orbit.   

       Option 2 - the track starts off horizontal, and just carries on dead straight, tangentially to the Earth's surface. As you travelled, you'd initially feel as if you were on a regular train (assuming the acceleration was much less than 1G) but, as you continued, you'd feel as if the train were tilting upward. After many thousands of miles, you'd feel as if the train were travelling straight up, with gravity pulling you onto the seatback (if you're facing forward). If you stepped off the train, you'd again fall back down, unless you were at the point of geostationary orbit. This would happen after your total distance of travel was slightly more than the radius of a geostationary orbit (you're travelling along the hypoteneuse of a long thin triangle; when the adjacent side of the triangle is as long as the radius of geostationary orbit, you're in geostationary orbit).   

       Option 3 - the track starts off horizontal, and carries on like a normal railway track, following the curvature of the earth in a great circle. In this case, if you remain on the train long enough you will come to Swindon, which is clearly not ideal. However, if the train can reach a speed of something like 8km/s, you will be in orbit, albeit at ground level. Sadly, the atmospheric compression will have long since melted the train. If you had a super-super ceramic unmeltable train, you would still have a problem because, if the train relied on contact between conventional wheels and the track for propulsion, it could never accelerate beyond this very-very-low orbit.   

       Option 4 - the track starts out horizontal, then curves toward the centre of the earth _but_ not as strongly as the earth's surface. Thus, you take a spiralling route outward. If the train can reach sufficient speed by the end of the track, it will continue in orbit. The bad news is that, unless the train has rockets that can change its velocity after it leaves the end of the track, its orbit will bring it right back to the end of the track and it will crash into it. This is true regardless of the train's speed as it leaves the track - a higher speed just means that it makes a more elongated elliptical orbit before returning to the end of the track.
MaxwellBuchanan, Feb 16 2013
  

       Those are very good, but unfortunately that's four and not three options, therefore being unable to count to four invalidates your assessment. Maybe someone with better numeracy will give it a try.
rcarty, Feb 16 2013
  

       [max] you could have a half-spiral inside Box Tunnel and the train could continue at more than 8km/s upside down.
pocmloc, Feb 16 2013
  

       [rcarty] there are 4 options; 3 extreme; therefore logically one must be realistic. Proved. Now to find out which one.
pocmloc, Feb 16 2013
  

       OK, here I am. I will fix it. Tracks held up above the surface of eath on struts or suspended by balloons seems wobbly, and that could be scary. Instead, the track begins at the surface but then allows the earth to curve up and over while it maintains a straight line. The depth of the tunnel at maximum will depend on how long of a track is necessary for the train to achieve escape velocity. Maximally long would go directly thru the earths center which would of course be unrealistic. Second longest would be one side of an equilateral triangle, the center of the triangle being the eath's core. Shorter tracks would be sides of increasingly sided polygons. After the use of math reveals how long the track must be, the appropriate polygon is selected and away you go!
bungston, Feb 16 2013
  

       That's the most ironic, counter-intuitive Space Train because it travels undeground like a subway, but also somehow to space.
rcarty, Feb 16 2013
  

       //that's four and not three options// No, because Option 1 is not feasible with current materials and, therefore, not an option.   

       // Second longest would be one side of an equilateral triangle, the center of the triangle being the eath's core.// No, second longest would be one that just grazed the core.   

       However, I wonder if all this engineering is strictly necessary. Much progress in psychiatry and climatology has been made by understanding and harnessing the placebo effect; perhaps it is time for physics and engineering to adopt a similar approach.
MaxwellBuchanan, Feb 16 2013
  

       Here's another hypothetical thought experiment that might satisfy those requirements: A scientist has a ball and some means of throwing it any speed and any trajectory. He knows the Earth is travelling through space rotationally at a certain speed and also orbitally at a certain speed and trajectory. He wants to throw the ball so the travel of the planet and the travel of the ball cancel the other out so the ball technically remains stationary and therefore ends up in space as the Earth continues on. The question: is it possible to throw a ball in space if Earth (and everyone on it) isn't going to be there.   

       Allow for the ball to be thrown from a train moving at the exact speed of the Earth in the opposite direction.
rcarty, Feb 16 2013
  

       Not possible. First, you need to define "stationary" relative to something. So let's say relative to the Sun (otherwise he will have also to allow for the motion of the sun in our galaxy, the motion of our galaxy in the universe, and... then there's nothing relative to which to measure velocity).   

       If he throws the ball in such a way that it remains stationary w.r.t. the Sun, it will simply fall directly into the Sun.
MaxwellBuchanan, Feb 16 2013
  

       What if the scientist reasons that something is to dark matter as an anchor is to the ocean, and employs that something to keep the ball stationary in space after deploying it from a hot air balloon powered by his own breath ?
rcarty, Feb 16 2013
  

       That's all well and good, but what if he doesn't? Answer me that.
MaxwellBuchanan, Feb 16 2013
  

       Simple. He tidies up a little around the house, eats a light supper, maybe reads a little and goes to bed.
rcarty, Feb 16 2013
  

       [marked-for-deletion] bad science.
FlyingToaster, Feb 16 2013
  

       Yes, but it's _our_ bad science.
Alterother, Feb 16 2013
  

       The only bit on a roller coaster that scares the crap out of me is the very beginning when the train is climbing that first hill at a painfully slow pace with attendant clanking and shaking. Just sayin'.
FlyingToaster, Feb 17 2013
  

       What happens if you have the Super Saver Space Train ticket and it turns out not to be valid because it's after 4pm on a Thursday in a month that has an "r" in it?
not_morrison_rm, Feb 17 2013
  
      
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