Author Topic: So, who wants to win 1 million Euro?  (Read 532255 times)

Offline Andromeda

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Re: So, who wants to win 1 million Euro?
« Reply #75 on: December 29, 2012, 03:38:49 AM »

So in Earth orbit the CSM was disconnected from the last stage of the Saturn rocket, rotated 180° and then connected to the Lunar Module?

Yes.


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And Walter did it?

Walter Cronkite was an American broadcast journalist for CBS News.  He described how the maneuver was completed to the American public on TV.  Why are you obsessed with him?!



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And then the CSM with the Lunar Module on top of the CM was sent off to the Moon.

Yes.



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Why not?

Does that mean you accept you were wrong?
"The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but 'That's funny...'" - Isaac Asimov.

Offline raven

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Re: So, who wants to win 1 million Euro?
« Reply #76 on: December 29, 2012, 03:41:49 AM »
At departure Earth the Command Module and the Service Module are together loaded on top of the Saturn rocket with the Lunar Module stored below the Service Module, actually below the rocket engine outlet of the Service Module.

After lift off and one orbit Earth the space ship is sent off towards the Moon and one way or another the Lunar Module is shifted to the top of the Command Module, so that later, in Moon orbit, two persons can enter it via the hatches. Can anybody explain how the transfer of the Lunar Module from below the Service Module to the top of the Command Module was done?
Two words, relative velocity. Once on a trans lunar trajectory, on the way to the moon, the LM, spent SIVb booster, and CSM were, relative to each other, standing still, in free fall. The RCS rockets, the cross shaped bunches of rocket nozzles on the Service module and lunar module, were more than enough to push it forward and around and back the minuscule amount of change in velocity to dock the LM with the CSM.
 lso, another thing you got wrong is that you don't need much, if any, fuel to change orientation, which way you are pointed along a particular trajectory, especially in a drag free, weightless environment like LEO or translunar trajectory..
Seriously, this kind of manoeuvring is necessary for any kind of docking with the ISS, or even constructing the ISS, something anyone who cares to look could go outside and see if they look up at the right time.

Offline nomuse

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Re: So, who wants to win 1 million Euro?
« Reply #77 on: December 29, 2012, 03:43:45 AM »
I vote "How did Walter do it" to the same wall of fame as "How far up does this alleged vacuum go" and "Who is this Jodie Banks person?"

Offline Heiwa

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Re: So, who wants to win 1 million Euro?
« Reply #78 on: December 29, 2012, 03:44:02 AM »
Space travel is in three dimensions with hugely varying mass and changing gravitational fields.  Neither of those apply to sailing.

Sailing in the interface air/water is evidently also in three dimensions and the forces applied to the sea going ship are much more complicated than those of a space ship.

As a sea going ship is always subject to resistance, a force N must be applied all the time to maintain a certain speed requiring fuel, etc, etc. Quite complicated. A space ship is not really subject to resistance and its speed is only affected by nearby masses (like Earth and Moon). However, to change speed of a space ship under controlled forms you need a force and to produce that force you need fuel.
Thus the same basic physical principles apply, I am happy to conclude.

Offline Andromeda

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Re: So, who wants to win 1 million Euro?
« Reply #79 on: December 29, 2012, 03:46:50 AM »
Space travel is in three dimensions with hugely varying mass and changing gravitational fields.  Neither of those apply to sailing.

Sailing in the interface air/water is evidently also in three dimensions

But the ship doesn't move in three dimensions.  It moves across the surface of the sea - two dimensions.

I note you do not respond to my points about changing mass and gravitational fields.

Thus, you know absolutely nothing about orbital mechanics or how to apply them, I am happy to conclude.
"The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but 'That's funny...'" - Isaac Asimov.

Offline nomuse

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Re: So, who wants to win 1 million Euro?
« Reply #80 on: December 29, 2012, 03:49:48 AM »

Space travel is similar to a voyage at sea (my speciality) and you need fuel to get from A to B.
If you study my presentation (topic - see post #1 with link to it) you see my concern is just the fuel used by Apollo 11 and ... after basic calculations using NASA input ... I find that Apollo 11 could not carry the required fuel to get in and out of Moon orbit. The space ship was too heavy or the engines to inefficient or something.
If you think my calculations are wrong, just show it. Do not tell me how stupid I am, etc, etc.

I am also curious to know how Walter managed to shift the Lunar Module in space from one end to the other of the CSM! Do you know, how Walter did it?

No.

Sea travel (with some exceptions!) is pre-Newtonian.  Space travel (with some exceptions) is Newtonian.  Even the best hull design on the water still has significant drag.  If you don't put in energy to offset the drag, you don't move forward.  Thus, all else being equal, energy and distance are interchangeable.  A phrase like "miles per gallon" makes sense.

In space travel, if you discount gravitational sources from the problem, there is essentially no drag.  You will travel for a very long time and for inconceivable distances before you need to put any energy into the spacecraft.  In this later case, energy and change of velocity are interchangeable. A phrase like "miles per gallon" is nonsense.

Offline Jason Thompson

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Re: So, who wants to win 1 million Euro?
« Reply #81 on: December 29, 2012, 03:51:26 AM »
Space travel is similar to a voyage at sea

What absolute rubbish. Space travel is a 3-dimensional problem involving a vehicle that substantially varies its mass during the voyage and spends most of it passively moving while being affected by gravity.

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my concern is just the fuel used by Apollo 11

Why specifically Apollo 11? What of the other unmanned probes I have mentioned, all of which had the same problem, namely getting into orbit around another celestial body?

You want to arbitrarily restrict the problem to one example of dozens, and you use calculations you already admit are wrong because you have not considered the varying mass of the spacecraft. You have been shown exactly where to get the correct figures you need for your calcuations, and where to find the correct calculations, yet you ignore that entirely. You are making elementary mistakes that no aerospace engineer would ever make. You know nothing of the subject material and you obviously have no intention of delievering on your promise to pay anyone who can prove you wrong, as evidenced by the way you continue to ignore those who have done so.

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I am also curious to know how Walter managed to shift the Lunar Module in space from one end to the other of the CSM! Do you know, how Walter did it?

I am curious as to why someone who claims to be an engineer who has studied Apollo does not know how this manoeuvre was accomplished, despite the reams of documents on the subject that are readily available, and its portrayal in at least one major movie and a TV miniseries.
"There's this idea that everyone's opinion is equally valid. My arse! Bloke who was a professor of dentistry for forty years does NOT have a debate with some eejit who removes his teeth with string and a door!"  - Dara O'Briain

Offline Heiwa

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Re: So, who wants to win 1 million Euro?
« Reply #82 on: December 29, 2012, 03:52:31 AM »

 lso, another thing you got wrong is that you don't need much, if any, fuel to change orientation, which way you are pointed along a particular trajectory, especially in a drag free, weightless environment like LEO or translunar trajectory..
Seriously, this kind of manoeuvring is necessary for any kind of docking with the ISS, or even constructing the ISS, something anyone who cares to look could go outside and see if they look up at the right time.

Evidently you do not need much energy to change the orientation of the moving space ship as you just rotate it around itself keeping an eye of the gyro.
The problem is to change direction and velocity, particularly to change velocity from, e.g. 2400 to 1500 m/s at arrival the Moon. According my calculations you need >46 000 kg of fuel to do it.

Offline Chew

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Re: So, who wants to win 1 million Euro?
« Reply #83 on: December 29, 2012, 03:52:47 AM »
The kinetic energy of a mass m = 43000 kg at velcocity v=2400 m/s is evidently 43 000*2400²/2= 123.84 GJ
At v=1500 m/s the kinetic energy is 48.375 GJ.
The difference in kinetic energy of a mass of 43000 kg at 2400 and 1500 m/s is therefore 123.84-48.375=75.465 GJ.
In order to reduce the velocity from 2400 to 1500 m/s, which takes a certain time t (seconds) you must apply a force F (Newton), while the space ship displaces a distance d (meter).
Say that the time t is 600 seconds? What is the force F? And the distance d? Show me that you can calculate.

The acceleration would be 1.5 m/s2 so the force is 64,500 N.
The distance would be the average velocity (assuming constant acceleration, which would not be the case) = 1,170,000 m.
The kinetic energy in joules would be 43,000 kg · 1,170,000 m · 1.5 m/s2 = 75.465 GJ.

Doing the same calculations with different velocities that differ by 900 m/s, say from 10,000 m/s to 9100 m/s, we get:
The acceleration would be the same: 900 m/s ÷ 600 s = 1.5 m/s2 so the force is the same.
The distance 5,730,000 m.
Kinetic energy = 43,000 kg · 5,730,000 m · 1.5 m/s2 = 369.585 GJ.
Using your equation kinetic energy is 43,000 kg · (10,0002 - 91002) ÷ 2 = 369.585 GJ, the exact same value.

But notice the acceleration remains the same, 1.5 m/s2, regardless of the initial velocity. It is force that accelerates a spacecraft, not energy. Force = mass · acceleration which means acceleration = force ÷ mass. Nowhere in this acceleration equation is there a place for energy.
« Last Edit: December 29, 2012, 04:12:46 AM by Chew »

Offline Heiwa

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Re: So, who wants to win 1 million Euro?
« Reply #84 on: December 29, 2012, 03:55:50 AM »


But the ship doesn't move in three dimensions.  It moves across the surface of the sea - two dimensions.



?? As I said a ship moves in the interface water/air and that interface is moving in 3-D. Ever heard about waves?
Only an ice skater moves on top of the 2-D surface of a frozen sea but when he/she jumps it is in 3-D.

Offline Jason Thompson

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Re: So, who wants to win 1 million Euro?
« Reply #85 on: December 29, 2012, 03:56:17 AM »
The problem is to change direction and velocity,

There's a nice tautology that doesn't seem likely to have come from an engineer. If you can't figure out why it is tautological I think that says all we need to knnow about your qualifications really.
"There's this idea that everyone's opinion is equally valid. My arse! Bloke who was a professor of dentistry for forty years does NOT have a debate with some eejit who removes his teeth with string and a door!"  - Dara O'Briain

Offline Jason Thompson

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Re: So, who wants to win 1 million Euro?
« Reply #86 on: December 29, 2012, 03:58:02 AM »
Ever heard about waves?
Only an ice skater moves on top of the 2-D surface of a frozen sea but when he/she jumps it is in 3-D.

But the point is that the ship does NOT jump, isn't it? The ship moving over waves does so passively. It has engines that can move it forward, backwards, left and right. Wave motion is not something it drives itself upwards or downwards to compensate for.
"There's this idea that everyone's opinion is equally valid. My arse! Bloke who was a professor of dentistry for forty years does NOT have a debate with some eejit who removes his teeth with string and a door!"  - Dara O'Briain

Offline Chew

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Re: So, who wants to win 1 million Euro?
« Reply #87 on: December 29, 2012, 03:58:18 AM »
And Walter did it?

The only Apollo astronauts named Walter were Schirra and Cunningham who both flew on Apollo 7, which you damn well know didn't fly with a LM, so stop your baiting.

Offline Andromeda

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Re: So, who wants to win 1 million Euro?
« Reply #88 on: December 29, 2012, 03:58:33 AM »


But the ship doesn't move in three dimensions.  It moves across the surface of the sea - two dimensions.



?? As I said a ship moves in the interface water/air and that interface is moving in 3-D. Ever heard about waves?
Only an ice skater moves on top of the 2-D surface of a frozen sea but when he/she jumps it is in 3-D.

Uh huh.  And how do you make a ship jump over waves, then?
"The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but 'That's funny...'" - Isaac Asimov.

Offline Chew

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Re: So, who wants to win 1 million Euro?
« Reply #89 on: December 29, 2012, 04:01:18 AM »

So in Earth orbit the CSM was disconnected from the last stage of the Saturn rocket, rotated 180° and then connected to the Lunar Module?

Yes.

No! With the exception of Apollo 9, transposition and docking took place after TLI.