Jump to content
Search In
  • More options...
Find results that contain...
Find results in...
Reisal

Mars One purported to be "sketchy, a scam"

Recommended Posts

Link

Well I am not surprised at all at this. I was a bit skeptical hearing this the first time and this further cements my doubts.

Share this post


Link to post

It would suck to be one of the first pioneers anyway. They should send remote-operated automatons to terraform the planet first, before sending humans to live there. But that probably wouldn't be possible anytime in the near future.

Share this post


Link to post

One giant red planet with a giant canyon which dwarfs the grand canyon, one giant red ball which could turn blue when the light settles.

Only one way, one way to go and watch in awe to then suffer in one brutal and lonely way, probably suffering a lot both mentaly and physicaly. 3 years to get there, if not longer. once they claimed a full life time but technology changed so it does not take one full lifetime.

One weird buisiness claiming to send anybody up there to die, knowing not one professional astronaut ever dared to try with the current technology. One serious nutcase is all we need to prove its possible.

One may dream, one may dream.

Share this post


Link to post

It's amazing that until now, voices of reason have been insulted, slammed, and silenced in the mainstream, and even in scientific publications.

Even more amazing is that voices of reason continue to be universally slammed on the topic of space elevators, an idea that's easily a million times more unfeasible than Mars One.

Share this post


Link to post
AndrewB said:

It's amazing that until now, voices of reason have been insulted, slammed, and silenced in the mainstream, and even in scientific publications.

Even more amazing is that voices of reason continue to be universally slammed on the topic of space elevators, an idea that's easily a million times more unfeasible than Mars One.


What's wrong with space elevators? True, we don't yet have a cable strong enough for them, but that kind of thing hardly out of the reach of potential advances in materials science.

Share this post


Link to post
AndrewB said:

It's amazing that until now, voices of reason have been insulted, slammed, and silenced in the mainstream, and even in scientific publications.

Did this really happen? I thought this was widely considered a hyped up startup with unsure results at best and a straightforward scam at worst. Daily Mail-style tabloid science shouldn't count and I've only ever seen that sort of coverage.

Share this post


Link to post
NoXion said:

What's wrong with space elevators?

A society that is technologically advanced enough to build a space elevator doesn't need a space elevator. The problems that the elevator would alleviate, heavy-lifting, would have needed to be dealt with in order to build it.

Share this post


Link to post
Quast said:

A society that is technologically advanced enough to build a space elevator doesn't need a space elevator. The problems that the elevator would alleviate, heavy-lifting, would have needed to be dealt with in order to build it.


I think that misapprehends what makes space elevators useful. It's not about heavy lifting per se - any fission-powered rocket will do that - but rather it's about efficiency. A fleet of rockets will consume fuel/propellant with every trip, whereas a space elevator only has to be built once and can then exchange energy between stuff going up and stuff going down with minimal losses.

It's like saying that railroads are useless because we have motor vehicles, when in fact both have their own sets of advantages and disadvantages making them useful in different situations. Heavy lift launch vehicles are good for when you need something quickly lifted into orbit, like transferring passengers from a spaceport on a planetary surface to a space station in orbit. Space elevators would be useful for providing a steady stream of materials to and from space in an efficient if not fast manner.

Share this post


Link to post
NoXion said:

What's wrong with space elevators? True, we don't yet have a cable strong enough for them, but that kind of thing hardly out of the reach of potential advances in materials science.

Strength isn't enough. Not only must the cable must be made of a material stronger than we've ever discovered, it must also be lighter than any material ever discovered (including gases), more rigid than any material ever discovered, and harder than any material than ever discovered. And even then, it has to break the previous record for these qualities by many orders of magnitude to even be considered suitable. And even then, there has to be a way to mass-produce this miracle fantasy material in a way that no material has ever been mass-produced before. And even then, there's no known way to actually get the elevator up there than to break it into millions of pieces and spend trillions of dollars and millions of tons of rocket fuel with thousands of missions into space to deliver the payload and weld each piece to the next one at a time. Wasn't the whole point of the space elevator to avoid wasting fuel on trips to space?

And like Quast said, if all those things were true, it would be such a world-changing miracle that the last thing on anyone's mind would be to build a rope to climb nowhere. It would literally make more sense to try to use the material to make a floating railway across the pacific ocean.


But your question really exemplifies what I'm saying. You've been reading articles that cast the idea in a non-skeptical light. This is what mainstream journalism does on topics it can't comprehend such as space travel.

Share this post


Link to post

I would love to see what happens when a space elevator sways around in the entry point of the atmosphere, something that large will sway a lot. It will have to resist the burning temperatures while swaying trough the atmospheric border, non stop. And the energy it might need...

And correct me if im wrong, space radiation radiating its way down the shafts for as far as it can get...

Share this post


Link to post
FireFish said:

I would love to see what happens when a space elevator sways around in the entry point of the atmosphere, something that large will sway a lot.

That's why the material must be prohibitively rigid and light, as well as the other properties mentioned. Like if diamonds, aerogel, and spider webs had a orgy, and that orgy produced a baby, and that baby was born in nuclear waste and had superpowers. That's pretty much the most realistic hope we have right now of ever getting a space elevator.

Share this post


Link to post

I take it then that carbon nanotube-based fibres are out of the question as a cable material? They would seem to have all right properties at first glance. There are plenty of extraterrestrial sources of carbon not in deep gravity wells (carbonaceous asteroids), and you could make it in orbit with just one orbital facility, coiling it up as it's made and then spooling it down from geostationary orbit when the full length of it has been made. You'd still need to expend fuel/propellant in order to build it, but once it's done you don't need to do that any more, whereas sticking solely with HLLVs requires fuel/propellant for every trip you ever make.

As for rigidity, aren't space elevators supposed to be under tension? A taut cable isn't going to flap about in the wind much, especially if A) it's attached to the ground and B) most of its length is not in an atmosphere to disturb it.

With regards to space radiation, how on Earth would it get from there to here? Wouldn't the structure of the elevator block/absorb it? Hell, the atmosphere absorbs the vast majority of it anyway under normal conditions. What would be different?

Share this post


Link to post
NoXion said:

I think that misapprehends what makes space elevators useful. It's not about heavy lifting per se - any fission-powered rocket will do that - but rather it's about efficiency. A fleet of rockets will consume fuel/propellant with every trip, whereas a space elevator only has to be built once and can then exchange energy between stuff going up and stuff going down with minimal losses.

That is an interesting way to look at it. I honestly never considered just how long an elevator would take to lift something into orbit. But that doesn't necessarily mean it is efficient. You'd be talking about a very large, gantry sized object or larger carrying 100s of Kgs of stuff into orbit. How much electricity is really required for such and undertaking?

It's like saying that railroads are useless because we have motor vehicles, when in fact both have their own sets of advantages and disadvantages making them useful in different situations.

Not at all. A more apt comparison would be if we wanted to build a steam locomotive network that required maglev train technological understanding.

What do you think is at the top of a space elevator? It would have to be a rather massive space station capable of handling the rather large cargo it would receive in addition to everything else. How does all that get into orbit and constructed in any reasonable timeframe without the elevator to begin with...or some other method of transportation which would have be superior to chemical rockets?

Share this post


Link to post
NoXion said:

As for rigidity, aren't space elevators supposed to be under tension?

Tension and rigidity are not the same thing. The material must be inherently rigid in the sense that the speed of sound inside the material is high enough that any vibration on one end of the structure quickly travels to the other end of the structure and back to resolve itself. When you're talking about structures in the 100,000km range, the speed of sound must at or very near the speed of light in order to prevent the structure from having strong vibrations on one end while having no vibrations at all on the other end. The more of an imbalance you have in this sense, the more violently and chaotically this will be equalized. Meaning that the tiniest amount of force will amplify across the length of the structure resulting in a chaotic, wacky waving whipsaw motion that ultimately (in the best case scenario) turns the structure into a tangled ball of wobbling stringy nonsense. The best estimate for the speed of sound in carbon nanotubes is a few dozen km/s. The speed of light is about 300,000 km/s. So the rigidity is a few orders of magnitude away from being adequate. And that's where the problem of density comes in. If you have a super strong, but also super rigid substance with a density that resembles that of Earth solids, the mass of the object will be so great that the vibrations that it experiences will exert so much energy that, like an earthquake 15.0 on the richter scale, it literally destroys any object that it touches. That's why a theoretical space elevator object must be made of an incredibly light, but solid material. Far lighter than helium. And it must be made in one solid piece: Screwing together pieces of this material would defeat the rigidity. It would be as pointless as this. The only way this would work is if you built the entire structure as one long 100,000km piece here on Earth, tied the whole thing to rockets and blasted it up to space in one go.

Share this post


Link to post
Quast said:

That is an interesting way to look at it. I honestly never considered just how long an elevator would take to lift something into orbit. But that doesn't necessarily mean it is efficient. You'd be talking about a very large, gantry sized object or larger carrying 100s of Kgs of stuff into orbit. How much electricity is really required for such and undertaking?


You could get at least some of the energy for sending things up by sending things down, as in a gigantic looped pulley.


Not at all. A more apt comparison would be if we wanted to build a steam locomotive network that required maglev train technological understanding.


Since steam expansion can be used even in nuclear reactor designs to drive turbines, I don't think we can categorically rule out certain engineering approaches just because they might appear "primitive". It's not as if the basic design of the wheel has changed drastically over the centuries - instead, it's been refined and specialised for many modern uses.

What do you think is at the top of a space elevator? It would have to be a rather massive space station capable of handling the rather large cargo it would receive in addition to everything else. How does all that get into orbit and constructed in any reasonable timeframe without the elevator to begin with...or some other method of transportation which would have be superior to chemical rockets?


The topstation would be part of the cost of the whole apparatus. You could reduce energy costs by sourcing materials from extraterrestrial bodies like with the cable itself. To be clear, I don't think that a space elevator could be built without some pre-existing orbital infrastructure, but the presence of that doesn't necessarily imply that "current" methods of transporting stuff from surface to orbit and vice versa are anything near perfect or universally applicable.

AndrewB said:

Tension and rigidity are not the same thing. The material must be inherently rigid in the sense that the speed of sound inside the material is high enough that any vibration on one end of the structure quickly travels to the other end of the structure and back to resolve itself. When you're talking about structures in the 100,000km range, the speed of sound must at or very near the speed of light in order to prevent the structure from having strong vibrations on one end while having no vibrations at all on the other end. The more of an imbalance you have in this sense, the more violently and chaotically this will be equalized. Meaning that the tiniest amount of force will amplify across the length of the structure resulting in a chaotic, wacky waving whipsaw motion that ultimately (in the best case scenario) turns the structure into a tangled ball of wobbling stringy nonsense. The best estimate for the speed of sound in carbon nanotubes is a few dozen km/s. The speed of light is about 300,000 km/s. So the rigidity is a few orders of magnitude away from being adequate. And that's where the problem of density comes in. If you have a super strong, but also super rigid substance with a density that resembles that of Earth solids, the mass of the object will be so great that the vibrations that it experiences will exert so much energy that, like an earthquake 15.0 on the richter scale, it literally destroys any object that it touches. That's why a theoretical space elevator object must be made of an incredibly light, but solid material. Far lighter than helium. And it must be made in one solid piece: Screwing together pieces of this material would defeat the rigidity. It would be as pointless as this. The only way this would work is if you built the entire structure as one long 100,000km piece here on Earth, tied the whole thing to rockets and blasted it up to space in one go.


So nothing could be done to dampen vibrations at all? No kind of dynamic stabilisation system is possible?

Share this post


Link to post
NoXion said:

So nothing could be done to dampen vibrations at all? No kind of dynamic stabilisation system is possible?


Let's start with a proof of concept. Start with a normal guitar string with tension so that it produces a normal sound. Now, without changing the tension, changing the string, or influencing it with a significant amount of outside mass such as a finger, prevent the string from making a sound when plucked. Any ideas?

Share this post


Link to post

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×