Author Topic: Please Explain the Velocity Numbers  (Read 35271 times)

Offline pleasedebunkme

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Re: Please Explain the Velocity Numbers
« Reply #45 on: May 24, 2013, 10:52:47 AM »
So, somewhere in the calculations, NASA had to account for the velocity of 1,000 m/s, which is the approximate velocity of the Moon in orbit around the Earth.  That is what I am looking for:  Where and how did NASA account for this velocity? 

Offline Glom

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Re: Please Explain the Velocity Numbers
« Reply #46 on: May 24, 2013, 11:25:59 AM »
So, somewhere in the calculations, NASA had to account for the velocity of 1,000 m/s, which is the approximate velocity of the Moon in orbit around the Earth.  That is what I am looking for:  Where and how did NASA account for this velocity? 

Sounds a very naive question.  In what exact form do you expect to see it?  It was incorporated into computer programmes used to plan and run the flight.  Any numpty these days can replicate that with their own computer program, even using just VBA.

Are you expecting to see it discussed in a chapter of some report like a chapter on economic forecasts in a Network Rail report into rail utilisation strategy?

Offline Chew

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Re: Please Explain the Velocity Numbers
« Reply #47 on: May 24, 2013, 11:52:10 AM »
So, somewhere in the calculations, NASA had to account for the velocity of 1,000 m/s, which is the approximate velocity of the Moon in orbit around the Earth.  That is what I am looking for:  Where and how did NASA account for this velocity? 

It was accounted for in the same way a skeet shooter hits a skeet, a quarterback passes to the receiver, or a submarine sinks a ship with a torpedo: by aiming at the point the target will be at when the projectile arrives.

Offline pleasedebunkme

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Re: Please Explain the Velocity Numbers
« Reply #48 on: May 24, 2013, 11:52:41 AM »
Also, retrograde motion is a direction, not a force.  As soon as the Apollo 11 direction changed, and it was no longer traveling retrograde relative to the Moon's orbital trajectory, then Apollo 11's velocity relative to the Earth should have been recalculated.  I think the way physics works is that an object in motion stays in motion, until a force is applied.  The retrograde motion on the back side of the Moon was not a braking force, and Apollo 11 would have retained its momentum.  So, I am back to the same question:    Back in 1969, did NASA forget to include the Moon’s orbital velocity when it computed Apollo 11’s return velocity to the Earth?  Telling me that the orbital velocity was included in some type of computer program does not answer the question, because the velocity numbers that NASA did provide back in 1969 do not include the Moon's orbital velocity. 

So, without insulting me by calling me naive, could someone please explain to me why the Moon's orbital velocity was not included. 

Also, since the subject has come up a couple times, could someone please explain to me how Apollo 11 could get all the way around to the antipode (or at least very close to it) without Apollo 11 being in some type of elliptical orbit?  It seems to me that an elliptical orbit is necessary, else Apollo 11 could never get all the way around to the antipode.  Thus, the question of when Apollo 11 entered that Earth orbit is very important.  It seems that we have come to some type of agreement that at the very least there was a stretch of the journey home for at least 16,000 km that Apollo was not in orbit around the Earth.  But, this calculation does not appear to include the movement of the Moon or the movement of the Earth.  So, my second question still has not been answered:  When and how did Apollo 11 regain its alleged elliptical orbit around the Earth that allowed it to use the alleged re-entry corridor?

Yes, I realize it is much more fun beating up lunar landing doubters on issues like lunar photographs and radiation belts, but the velocity numbers are much more important. 

Thank you for your consideration. 

Offline scooter

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Re: Please Explain the Velocity Numbers
« Reply #49 on: May 24, 2013, 01:01:06 PM »
They knew the gravitational force of the Moon. They knew the gravitational force of the Earth.

Even in lunar orbit, the Earth's gravity slightly perturbs an object orbiting the Moon...and vice versa. It's a function of distance from the attracting body, and the mass of that body.

The orbital velocity of the Moon around Earth was not a factor, escape velocity is the same for prograde, retrograde, polar, whatever. The "surface" speeds are different for different orbit inclinations (due to parent body rotation), but that's not a factor. The velocity for an "escape" is also the same, and, given a burn approximately opposite  the target body, the trajectory will be the same, as the Moon's gravitational effect lessens and the Earth's gravity influence increases. 
How quickly the Moon is rotating around the Earth isn't important. The trajectory is based on the bodies as "massive" objects, and the impulse and vector applied to the object.
The TEI burn simply created a highly elliptical orbit with an apolune (is that right?) high enough to allow Earth's gravity to appropriately dominate and "capture" the craft.
Hoping I have this all correct, instruction always welcome.

Offline gillianren

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Re: Please Explain the Velocity Numbers
« Reply #50 on: May 24, 2013, 01:06:50 PM »
Yes, I realize it is much more fun beating up lunar landing doubters on issues like lunar photographs and radiation belts, but the velocity numbers are much more important. 

Yes, they are, but they also take a lot more effort to understand.  You seem to want orbital mechanics to be simple, and I don't understand why.
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Offline Jason Thompson

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Re: Please Explain the Velocity Numbers
« Reply #51 on: May 24, 2013, 01:11:14 PM »
As soon as the Apollo 11 direction changed, and it was no longer traveling retrograde relative to the Moon's orbital trajectory, then Apollo 11's velocity relative to the Earth should have been recalculated.

And how do you know it was not?

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The retrograde motion on the back side of the Moon was not a braking force, and Apollo 11 would have retained its momentum.

Before going down this road, consider how Apollo 11's (or indeed any lunar orbiting vehicle's) velocity relative to the Earth is constantly changing since it is going in a roughly equatorial, roughly circular orbit around the Moon. Using the figures you quoted, of an orbital speed of 1,624 m/s, and the Moon's approximately 1,000 m/s orbital speed, that would mean that at the point where the spacecraft is directly between Earth and moon in its orbit it is going at 2,624 m/s relative to Earth, and on the other side of its orbit it is going at 624 m/s in the other direction relative to Earth. It's not a braking force, but the Moon's gravity acting on the spacecraft to keep it in orbit is affecting its velocity relative to the Earth.

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Back in 1969, did NASA forget to include the Moon’s orbital velocity when it computed Apollo 11’s return velocity to the Earth?

No, because if they had none of the flights would have worked.

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Telling me that the orbital velocity was included in some type of computer program does not answer the question, because the velocity numbers that NASA did provide back in 1969 do not include the Moon's orbital velocity.

According to you, and your own expectations of what they should have included and where that should be apparent. You've been advised to look into the two- and three-body problems of orbital mechanics. Those will answer your questions.

Do you at least acknowledge that the location of the TEI burn makes your original calculation of relative speed wrong, since you simply added the spacecraft's orbital velocity rather than subtracting it as you should have? Do you also understand that having escape velocity doesn't help you if your trajectory is aimed right at the thinig you are trying to escape from?

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So, without insulting me by calling me naive, could someone please explain to me why the Moon's orbital velocity was not included.

It was included in the calculations. Your expectation of where that should be apparent is at fault.
 
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It seems to me that an elliptical orbit is necessary, else Apollo 11 could never get all the way around to the antipode.

It can if it passes close enough to the Earth.
« Last Edit: May 24, 2013, 01:37:49 PM by Jason Thompson »
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Offline scooter

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Re: Please Explain the Velocity Numbers
« Reply #52 on: May 24, 2013, 01:18:32 PM »
So, somewhere in the calculations, NASA had to account for the velocity of 1,000 m/s, which is the approximate velocity of the Moon in orbit around the Earth.  That is what I am looking for:  Where and how did NASA account for this velocity?

As I understand it, this would affect where the returning craft actually reentered and landed on Earth. Between the Moon's orbit around the Earth, and where the TEI occurred in that Moon orbit around the Earth, added to the Earth's rotation, and the resulting reentry cooridor, there were a lot of numbers to be crunched to sort out these variables. They obviously accounted for these numbers, including calculating for TEI burns 1 or 2 lunar orbits ahead of/behind the "scheduled" TEI burn.

They were very, very talented people.

Offline Luckmeister

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Re: Please Explain the Velocity Numbers
« Reply #53 on: May 24, 2013, 04:06:30 PM »
pleasedebunkme, you have received more than adequate answers with a lot of thought and expertise put into them. It appears that you did not come here for answers but to repeatedly plant seeds of doubt regarding Apollo veracity.

Scientifically and historically, the null hypothesis is that the missions were successful. That puts the burden of proof squarely upon your shoulders to provide evidence (maths, etc.) that the Apollo 8, and 10 through 17 spacecrafts could not have safely returned to Earth. It's time you start doing that, as Echnaton requested back in Post #36, instead of repeating questions while ignoring or rejecting the good answers you have been given; otherwise you are just wasting everyone's time here.

Since you obviously question the reality of the 9 Apollo missions that returned people from the Moon, then I ask you to go to http://en.wikipedia.org/wiki/List_of_Apollo_missions and look at what is just an overview of what those missions entailed. How can you even conceive of the possibility that it all could have been faked? There's really no wonder that members here find it difficult to give you the respect you feel you deserve....and yet, most of them have. That's to their credit, not yours.
« Last Edit: May 24, 2013, 05:01:16 PM by Luckmeister »
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Offline PUshift

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Re: Please Explain the Velocity Numbers
« Reply #54 on: May 24, 2013, 04:30:04 PM »
The retrograde motion on the back side of the Moon was not a braking force, and Apollo 11 would have retained its momentum.  So, I am back to the same question:    Back in 1969, did NASA forget to include the Moon’s orbital velocity when it computed Apollo 11’s return velocity to the Earth?

No, it was a braking force, and Apollo 11 has not retained its momentum - in respect to Earth´s orbital velocity, not the Moon’s .
The direction of TEI is important to go for a lower velocity in Earth´s orbit.
Decreasing velocity (makes your current position to apogee) lowers down the opposite orbit-side (hello perigee), where you will arrive half a round later at reentry.

The fact, that this TEI-direction also points against Moon´s orbital path appears rather implicit than the ultimate cause.
We had to do that even without a moon (slowing down in earth´s orbit).
The well planned escape path affected by the Moon´s gravity was obviously taken into account by leading into an inbound direction to earth which further lead to a 'plane-switch' which is the slingshot-thing.
First you are heading to the "left side" of earth (+/- 270° Incl), then it shifts over to the "right side" (+/- 0° Incl). This passive maneuver was only possible by the assist of a body like the Moon.

So the answer to your question is no. They did not forget anything.
They probably returned safely to Earth, at least there is much evidence which supports that claim.  ;)

pleasedebunkme, this starts to run in circles now. You want some detailed information as proof and nobody provides that. It´s because they are not willing to do your homework and research. Extraordinary claims require extraordinary explications, you must have heard that already, don´t ya? Please change your username. It makes no sense at all.

Offline Mag40

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Re: Please Explain the Velocity Numbers
« Reply #55 on: May 24, 2013, 04:59:59 PM »

Offline Echnaton

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Re: Please Explain the Velocity Numbers
« Reply #56 on: May 24, 2013, 07:09:02 PM »
Back in 1969, did NASA forget to include the Moon’s orbital velocity when it computed Apollo 11’s return velocity to the Earth?
No.

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the velocity numbers that NASA did provide back in 1969 do not include the Moon's orbital velocity. 

Oh really?  What is your source for that statement?  What searchs have you done? 
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It seems to me that an elliptical orbit is necessary

If I understand things correctly, all orbits around a body in space are elliptical.  What kind of orbit are you suggesting they were in and how did you determine that?

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the velocity numbers are much more important. 

More important for what? Showing that there was a hoax?  You haven't done that yet so it is premature to say that one piece of a non-proof is more important than another. 
The sun shone, having no alternative, on the nothing new. —Samuel Beckett

Offline Sus_pilot

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Please Explain the Velocity Numbers
« Reply #57 on: May 24, 2013, 09:31:14 PM »


That's what I'm starting to think.

Waiting for bluegrass banjo to start...

Offline scooter

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Re: Please Explain the Velocity Numbers
« Reply #58 on: May 24, 2013, 09:44:23 PM »
As I understand it, with the craft in orbit around a body (Moon) orbiting the target body (Earth)...the velocity of the Moon isn't a factor...it's gaining velocity around the Moon to acheive escape velocity from the Moon that's the issue, the Moon's orbital velocity isn't a factor in the TEI problem.

Offline ka9q

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Re: Please Explain the Velocity Numbers
« Reply #59 on: May 25, 2013, 01:46:07 AM »
The retrograde motion on the back side of the Moon was not a braking force, and Apollo 11 would have retained its momentum.
How can you possibly say this?

You do understand Newton's laws of motion, right? In particular, you understand that the momentum of a closed system remains constant, right? During the TEI burn, Apollo expels a considerable fraction of its mass in one direction at high velocity, so how could its momentum possibly remain unchanged?