? • Doubts: Space travel, artificial earth satellites, Hubble telescope &c

Doubts: Space travel, space rockets and launches, artificial earth satellites, Hubble telescope &c

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Doubts: Space travel, artificial earth satellites, Hubble &c

Postby FirstClassSkeptic » 28 May 2011 02:35

This thread is meant to replace the one 'there are no satellites' that is locked. Let's have a technical discussion only. I don't want to hear about all of those secretive groups.

I have doubts that NASA can get heavy payloads into a vacuum. It appears to me, from watching Apollo rocket launches, that a rocket engine works just like a propeller on an airplane; by moving lots of air. When they get into a vacuum, they fizzle. So they might move a light payload. But no landing four ton crafts on the moon, and no rover on Mars.

One puzzlement: The nozzle. All the rockets NASA pictures as going into space, like the lunar module, the service module, have a nozzle on them. Since the nozzle is supposed to adjust to air pressure, it would have to be infinitely big for zero air pressure. It would make more sense to have no nozzle at all.

One suspect: In rocket calculations, they use the exhaust gas velocity. However, this parameter is not measured empirically. What they do is put a rocket engine on a test platform, fire it, and measure the thrust (in an atmosphere) and the flow rate of fuel and air (Mass flow rate) They then calculate an effective exhaust velocity which they then use in their calculations. It's doubtful to me that the exhaust achieves the velocity they claim. It also doesn't prove it will operate in a vacuum.

Satellites: Definitely something up there. But, how high? Are they held there my Newtonian mechanics, as claimed, or by something else? Are they even out of the atmosphere?

Far side of moon pictures; The first pictures by the Luna craft of Russia look to me like close up pictures of rusted, pitted steel. I doubt that any far side picture is genuine. Close up pictures claimed to be from a lunar orbitor of the near side of the moon could just be computer filtered/enhanced pictures. Pictures of earth's deserts could be used to fabricate or simulate the lunar surface of the far side, or fill in unknown details of the near side. (Which might explain some of the structures claimed to be spotted by some, who say there are moon bases on the far side of the moon. It might just be a building in Arizona.)

Mars rover pictures: If you put them into a image editor and turn down the red drive, the pictures claimed to be from a Mars rover take on an earthly appearance, with blue or white sky.
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Re: Doubts about space travel, artificial earth satellites,

Postby rerevisionist » 28 May 2011 16:22

I have doubts that NASA can get heavy payloads into a vacuum. It appears to me, from watching Apollo rocket launches, that a rocket engine works just like a propeller on an airplane; by moving lots of air. When they get into a vacuum, they fizzle. So they might move a light payload. But no landing four ton crafts on the moon, and no rover on Mars.

I think you're making heavy weather of this. Let's just consider the problem of a rocket with a payload launching and going through space. I'll use a book edited by Andrews & McClone (1977 - not long after the supposed lunar landings, which were themselves preceded by Intelsat, from 1965. The Space Shuttles started after the lunar stuff had been closed - and must therefore be suspected as another scam). Here's the cover-design to add visual interest.
Image

According to my '1985 World Satellite Almanac', a typical satellite weighed about a ton, had a planned life of about ten years, and is kept in orbit by occasional squirts of compressed air - think 'Robot Wars' where robots use remotely-controlled compressed air cylinders.

B. Noble, of Wisconsin and Oxford, contributed the chapter 'Why Build Three-Stage Rockets?' which is easy enough to understand, though the maths uses calculus - as the fuel gets used up, the total weight drops, so there's a slow exponential change. It's quite easy to understand the general outline, if not the algebra - it isn't rocket science! [Hilarious pun intended].

[1] Conservation of momentum. The point here is that in free space any action has an equal and opposite reaction. (How difficult it is to word these things...) Imagine you're in an office chair on wheels, preferably on an icerink, and not allowed to put your foot on the ice. If you contact another such office chair, maybe pushing against it, if the weights are the same they will move apart in a fairly obvious way - there's no reason one gets priority. If someone shoots a gun or throws a ball, his chair moves in the opposite direction. The actual effect depends on the weights (or masses) of the various parts of the system. E.g. if one chair and person is very heavy, it'll move more slowly. Or imagine billard balls colliding; or hot air balloons. This would work in a vacuum. In space you don't need the rink - you can be in free fall, and as long as you're not going towards the earth you'll orbit it.

Momentum is measured by mass x speed. A rocket works by in effect projecting part of itself away. However exhaust gases don't weigh much. Hence the trick is to get them moving as fast as possible. This needs expansion and hence the use of special fuels, which typically get very hot. (The argument also applies to jet engines - BUT in the upper atmosphere these would need oxygen, which adds to the weight and engineering problems).

[2] Empirical Facts. B. Noble gives these facts (altered from metric system; I don't think they can be very outdated)---
(1) A satellite (or anything else) in orbit round the earth a few hundred miles up, moves at about 5 miles/second.
(2) The approx typical speed of expelled rocket gases is about 2 miles/sec.
(3) '... it is difficult to build engines and fuel containers with a total mass less than about an eighth to a tenth of the weight of the fuel.'
(4) With a one-stage rocket, ''When the fuel is almost exhausted, the engine is expending most of its effort on accelerating and almost empty fuel tank.'

Note that (2) and (3) are empirical - for engineering reasons, they apply. (1) is a consequence of the earth's gravity; (4) assumes the payroll weighs much less than the rocket's structures.

[3] Deductions applied to stages of rockets. Noble considers a one-stage rocket which however burns away continuously, so there's no deadweight of fuel container. With the assumption that empty weight: original full weight is about one in ten, he derives payload approx = 1/50th of full weight. A 50-ton rocket of this type could launch a 1 ton payload - assuming the assumptions apply.

[4] Approximating the idealised rocket. Dropping the assumption of a fuel container which burns away, Noble calculates the ratio of payload weight to rocket weight, and derives this table--

Number of stages .. 1 | ...2 | ..3 | .4 |....
Ratio ............... ---- | 149 | 77 | 65 | ...

A single-stage rocket can't get up to speed. A three-stage rocket can - and lifting a 1-ton payload uses fuel at about 20 tons/minute.

[5] Possible Problems. Noble selects a payload of 1 ton, which is OK for satellites. However there must be scaling problems with heavier items. If a rocket is doubled in every dimension, the areas quadruple, and the weights multiply by 8. There are engineering difficulties analogous to those in nature, which cause elephants to have hefty bones and big feet. If the payload is (say) 5 tons - I think this was something like Apollo 11- there would be problems. Skylab is, or was supposed, to weigh about 1 million pounds - about 500 tons. A B52 can take about 40 tons. This is why personally I believe in satellites, but am open to arguments that space stations are impractical and may have been faked. In fact, possibly Noble avoided the issue of heavier payloads for that very reason.

FirstClassSkeptic considers the question of 'push' against air. This seems correct - in the same way that falling into water from a height is dangerous - the water hasn't got time to move - air isn't completely compressible - a bird's wing pushes against air. I don't know if this is considered in detail in calculations, or whether air resistance is.

The definitive pre-lunar 'landings' rocket calculations book is Ball and Osborne (1967) - 'recommended for the serious student rather than the casual reader.' This book predates the 'space shuttle' practice, with its (alleged) rather low orbit, though the idea must have been considered.
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Re: Doubts about space travel, artificial earth satellites,

Postby FirstClassSkeptic » 28 May 2011 19:18

rerevisionist wrote:
According to my '1985 World Satellite Almanac', a typical satellite weighs about a ton, has a planned life of about ten years, and is kept in orbit by occasional squirts of compressed air - think 'Robot Wars' where robots use remotely-controlled compressed air cylinders'


Let me look at just this one thing for now, because it caught my attention.

I'm familiar with electronics, and with hybrid-microelectronics, which is transistors and IC's without the encapsulation of plastic, thus making them much smaller. Since an artificial satellite is basically an electronic device, I can't see why it would weigh a ton, or anywhere close to that.

A weather satellite with a camera, a transmitter, some solar panels, maybe a hundred pounds. A mono-filament wound sphere of compressed gas, maybe two pounds.
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Re: Doubts about space travel, artificial earth satellites,

Postby rerevisionist » 28 May 2011 20:02

OK - give it a good look, esp the supposed loads of the space shuttle.

Bear in mind I'm using rather old material, mainly to keep within range of the nuclear stuff and moon landing. I'd guess miniaturisation has come a long way in 25 years. But then again, so must the number of broadcast channels and general volume of traffic.
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Re: Doubts about space travel, artificial earth satellites,

Postby FirstClassSkeptic » 28 May 2011 23:47

OK, maybe I went off on a tangent there. My first reason for thinking they can't put heavy payloads into space is that if they could, they would.

If they actually could have put a payload on the moon, and then brought it back, they wouldn't have had to fake it. Or not a living payload, anyway. I have never heard of them sending a robot to the moon to scoop up rock and bring it back. Have they?

And if they could put a rover on Mars, they would, but I don't believe they have; they just faked it. And they wouldn't have to fake it if they could actually do it.

I don't know if any space walks, space stations, dockings, or what have you, that are photographed, are actually in space. I am convinced that Ed White's "space walk" wasn't in space.

So that leaves satellites. But how heavy is a satellite? Even at one ton, they are lighter than rovers and lunar landing craft.

And that leaves me unconvinced that NASA has ever put anything heavy into space. I mean, as heavy as they claim.

Picture of GPS satellite being assembled at Boeing.
https://www.insidegnss.com/auto/popupima ... y-Flag.jpg

But how do I know if it's for real?
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Re: Doubts about space travel, artificial earth satellites,

Postby rerevisionist » 29 May 2011 03:21

I'm happy with small satellites, but like you I have serious doubts about huge items. If you consider airplanes, there have been attempts at record sizes and record lifts, but there hasn't been linear progress. I haven't seen any thorough treatment of this problem, but the fact that planes don't seem able to increase in size forever suggests a scale problem. (Birds, and insects, must have the same difficulty - there are upper limits to sizes, unlike with fish, whch can simply keep growing).

I'd guess we could look at it in a simplified way: I presume an airplane's lift depends on its wing area, and speed. I don't know enough about jet engines to confidently state any limits, but the fact the blades can fragment on rotation suggests their diameter can't be bigger than a certain amount. So, suppose a plane were to be built, scaled up to three times the length, width, and height of a current plane. It could weigh 27 times as much - maybe more since the stresses would apply over a gretaer length. But it would have only 9 times the wing area. And it would need 27 times as much power, with engines which couldn't be much bigger than the current model, suggesting it would need 27 separate engines. But even then the lift would be too low by a factor of three.

There are other possibilities: imagine a tower several miles high, with a winch, to hoist up a space station and some sort of booster... hmm! Or a giant helium balloon to lift it onto an aerial platform. Or magnet-assisted lift, which however would probably only help at lift-off.

It wouldn't surprise me at all to find there's a definite upper limit, known to people in the business. And if the thing were put in orbit in pieces, tracking them down, collecting them together, and fitting them together would not be easy! Nor would getting the people home - it would be a long way to parachute! So my guess is space stations no, fake space walks in zero gravity in planes yes, launches of a few tons yes.

SPACE CADETS
Note: a TV station in Britain, Channel 4, ran, over some weeks, a series called 'Space Cadets'. They made over a base in Britain somewhere, so it looked Russian - this included replacing all the power points and fittings with Russian ones, putting signs in Russian everywhere, having I suppose Russian books, even strewing Russian litter wrappings about. The Russian-speaking actors gave 'training talks' to a bunch of young people. A special effects man with a team built a 'module' on hydraulic supports to mimic a moving body - it didn't seem realistic to me, as it bucked and kicked a bit, but psychologically that seemed right. And there was a window from which an arrangement of lights displayed a realistic-looking earth. The whole thing was filmed - arrival, training, and time in the 'module' - and the crew of 'cadets' all fell for it. There was a 'debriefing' when the hoax was revealed to them. Worth a ponder. I'd guess it's available on DVD though I haven't checked.

Parts of this are on Youtube though I couldn't find a full-length show - but here's a set of 10-minute parts, showing a summary of the 'training' and the 'launch' and orbiter activities. Well worth watching. (NB it is *possible* the whole thing was a set-up with actors, though it seems unlikely). The whole thing may have been suggested by the moon landings hoax.

https://www.youtube.com/watch?v=m4wgJ3A2HnY
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Re: Doubts about space travel, artificial earth satellites,

Postby rerevisionist » 29 May 2011 09:37

British Interplanetary Society
has or had a big building in south London. Looking back, this must have been part of the process of suppressing awkward facts about the difficulties of space travel. I don't suppose it was founded like that, but probably was taken over - no doubt NASA or wepaons interests funded it. It's clear form their website that it's just another junk organisation; there appears to be no honest appraisal of moon or Mars 'missions', for example. Just more prostitutes for pseudo-science. Ugh.

Maybe it deserves a separate thread; especially if someone out there has inside info.
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Re: Doubts about space travel, artificial earth satellites,

Postby FirstClassSkeptic » 30 May 2011 13:09

Some interesting pictures here of martian Rover:
https://www.rense.com/general78/rsm.htm

Not what I was looking for exactly.

There's something interesting I noticed a few years back when perusing a chart showing the specs of different aircraft, and that was that an aircraft has roughtly, very roughly, one horsepower per ten pounds of gross weight, and it didn't matter if if was a propeller, jet or helicopter.

I'll see if I can find that chart. I think it's in one of my books.

Here's a helicopter spec table.

https://www.helicopterpage.com/html/specs.html
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Re: Doubts about space travel, artificial earth satellites,

Postby rerevisionist » 30 May 2011 21:49

Yep @ FirstClassSkeptic. I'm not sure about jets, but helicopters and planes use similar mechanisms and within scalable limits would have similar power:weight ratio. The problems start with much bigger, or much smaller, devices.

I was thinking about rockets and suggest the following (maybe wrong - don't hold me to it). Suppose you have a workable rocket and want to scale it up three times linearly. I pick 3 times to emphasise the effect. Then we have roughly 27 times the weight, nine times surface areas, three times lengths. Now a rocket engine chucks out hot gas, the faster the more effective. A nozzle scales up in power as to surface area, I think. I mean - a nozzle three times in diameter needs to shove nine times as much gas through to get the same level of thrust, and that's OK, it scales up. But the weight has gone up 27 times, so you'll need three times as many scaled-up nozzles as the original. You'll run out of room for them, or run out of fuel earlier. (It's analogous to an insect increasing in size - oxygen can't diffuse fast enough to its internal organs if the design is unchanged. Another analogy is scaling from cars up to trucks: the area of the tires/tyres on the ground varies as a square, but the weight as a cube; so you need more and bigger wheels - trucks often have, say, 12 large tires/tyres, as opposed to four small ones on cars). No doubt booster rockets help; but with truly massive weights I think there's a real problem.

Your Martian dust reference from Rense is quite amusing. It just shows how hard it is to think of everything. Maybe NASA got a Mexican maid to dust their equipment or something.

Talking of not thinking of everything, one unexplored line of attack on NASA and the moon is the biological side. Apollo 11 supposedly took about 7 days for its round trip; three men would need enough air, water, food and excretion for seven days and each of these is problematic, especially air, or oxygen, which can only be stored by heavy equipment. In a perfect vacuum there would be problems... this would make a terrific video, in fact.
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Re: Doubts about space travel, artificial earth satellites,

Postby FirstClassSkeptic » 31 May 2011 02:34

Hubble picture of Apollo 17 landing site.

https://hubblesite.org/gallery/album/pr2005029g/

If a telescope were just in a high altitude jet it would get a clearer picture. It wouldn't have to be as high as NASA says it is.

Hubble orbits the Earth about every 97 minutes at an altitude of about 353 miles (569 kilometers).


https://hubblesite.org/hubble_discoverie ... de05.shtml
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Re: Doubts about space travel, artificial earth satellites,

Postby FirstClassSkeptic » 04 Jun 2011 20:21

https://www.dailymail.co.uk/sciencetech/ ... phere.html

Danish amateur space race blasts off as enthusiasts launch 30ft, 1.6 ton rocket five miles into the atmosphere

Their plan was for the rocket, which they have named after 16th century Danish astronomer Tycho Brahe, to reach a height of 10 miles (16km).

We'll take that: The plan was for the rocket to reach a height of 10 miles - however it only managed to get to the five-mile mark


So, why did it only go five? They don't give an explanation. They don't say anything went wrong. They don't say their calculations were wrong.
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Re: Doubts about space travel, artificial earth satellites,

Postby rerevisionist » 19 Jun 2011 12:39

Technical note on admin: When a topic appears twice - i.e. it's moved, but the 'shadow topic' is left behind - generally to reclassify a forum thread - the shadow is still linked to the moved topic. If the 'shadow' is deleted, so is the moved topic. I found this out try to delete a forum thread on 'No artificial satellites', which is now gone, though I have backup copies. To remove it, TRY moving the 'shadow' first - maybe to the same forum thread as the moved topic. Unfortunately the instructions, as is usual with computer techie stuff, aren't clear.

I think I'll replace the essence of it if I have time, and notably the Catholic conspiracy ideas presented as an alternative to ZOG.
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