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peter eldergill
2005-Aug-18, 03:46 AM
The idea that the astronaughts left a reflecting mirror of some sort on the moon so we can check distance seems impossible to me. How could it be such an accurate reflection over such a large distance? Off by a tiny fraction of a degree and your radio wave would not be returned to the proper spot.

Can someone explain how this works for me? Or are you all in on the conspiracy :P

Later

Pete

PhantomWolf
2005-Aug-18, 03:54 AM
The reflectors are corner cubes, basically a prism that will reflect any light tht hits it directly back at the source. It's not really an unusual technology, it's used for car and bike reflectors as well as the cats-eyes on the road and in a lot of over applications. The Apollo reflectors were just much bigger, about a metre square.

The second trick is that while lasers are highly tight beams, over the distance that beam has spread out to around a kilometer in diameter, so it just needs to be roughly in the right area and whatever light hits the relector will be returned.

Because it doesn't nmatter what angle it hits the light is returned to the source, the positioning doesn't matter a great deal to the ability to reurn, but it does to the ammount of light. The USSR reflectors were placed by remote contolled rover and they aren't aligned properly so they hve a smaller profile and thus reflect less of the light because less light is able to hit them. The Apollo reflectors were aligned by hand and so their full profile is hit returning a greater amount of the light.

Hope that helps.

peter eldergill
2005-Aug-18, 03:58 AM
It helps out for sure. THat is exactly the explanation I needed.

If this can be observed, then why isn't it enough to show to HB's that we have actually been on the moon?

L8R

Pete

Time to watch the Daily Show!

PhantomWolf
2005-Aug-18, 04:07 AM
It helps out for sure. THat is exactly the explanation I needed.

If this can be observed, then why isn't it enough to show to HB's that we have actually been on the moon?

L8R

Pete

Time to watch the Daily Show!

Because most ignore just totally it? When pointed out most of them will claim that regardless of the perfect alignment, they were placed there by unmanned probes like the Soviet's did. One of two try out Bart's claims tht they were already bouncing lasers off the moon in the 50's (not possible because the laser ws first built in 1960.) The basic answer is that while they claim otherwise, most HBs don't want to believe, or at least they want to only believe in what suits their ideological view of the world where The Government is out to get everyone through lying about everything.

ranb
2005-Aug-18, 04:08 AM
http://physics.ucsd.edu/~tmurphy/apollo/lrrr.html

Here is a good link. Instead of using a flat mirror, a set of cube shaped ones are mounted together to reflect the lazer back in the same direction it came from.

Ranb

Enzp
2005-Aug-18, 04:12 AM
Because no amount of evidence will overcome their desire for it not to be true.

They will inevitably offer arguments like:

Well if the Russians put up reflectors there without landing a human, why couldn't we?

Or: it is a trick, the lasers are not really reflecting.

Or: We just happened to discover a reflective patch of moon rock and are now claiming we put it there.

It doesn't matter, they will always find an objection or make one up.

Kiwi
2005-Aug-18, 08:29 AM
to reflect the lazer back

You're kidding! "Stimulated" does not start with "z." :D

Mr Gorsky
2005-Aug-18, 12:09 PM
to reflect the lazer back

You're kidding! "Stimulated" does not start with "z." :D

Hmm ... depends how much beer you drink ...

:D

Bob B.
2005-Aug-18, 01:35 PM
If this can be observed, then why isn't it enough to show to HB's that we have actually been on the moon?
Because the HBs don't want to believe we landed on the Moon. Facts and evidence have nothing to do with it.

montebianco
2005-Aug-18, 01:53 PM
most HBs don't want to believe, or at least they want to only believe in what suits their ideological view of the world where The Government is out to get everyone through lying about everything.

Well, governments do lie a lot, but they don't seem to be very good at it...

jrkeller
2005-Aug-18, 02:01 PM
In the words of Homer Simpson

Facts are meaningless

PhantomWolf
2005-Aug-18, 02:14 PM
most HBs don't want to believe, or at least they want to only believe in what suits their ideological view of the world where The Government is out to get everyone through lying about everything.

Well, governments do lie a lot, but they don't seem to be very good at it...
Yeah they do, unfortunately, but most CT's seem to be firmly of the opinion that when a politian speaks, he's lying. Therefore is a government official says 'X' the truth is actually 'Y'. They don't seem to be able to fathom that on occasion the Governments of the world do actually tell the truth.

jrkeller
2005-Aug-18, 02:33 PM
Because the HBs don't want to believe we landed on the Moon.


And because of that they can make a fast buck trying to convince others of the same thing.

NEOWatcher
2005-Aug-18, 02:42 PM
[snip] The Government is out to get everyone through lying about everything.

Well, governments do lie a lot, but they don't seem to be very good at it...
Yeah they do, unfortunately, but most CT's seem to be firmly of the opinion that when a politian speaks, he's lying. Therefore is a government official says 'X' the truth is actually 'Y'. They don't seem to be able to fathom that on occasion the Governments of the world do actually tell the truth.
And it is expected that a politician lies. I heard on the radio (not sure if it's true, but a trustworthy show) that in Canada somewhere, someone tried to sue a politician for lying. The politician made promises during the campain, then went against those promises. The judge denied the suit because campain promises are not expected to be kept.
It would be nice to hear the real story...

montebianco
2005-Aug-18, 02:48 PM
Well, governments do lie a lot, but they don't seem to be very good at it...
Yeah they do, unfortunately, but most CT's seem to be firmly of the opinion that when a politian speaks, he's lying. Therefore is a government official says 'X' the truth is actually 'Y'. They don't seem to be able to fathom that on occasion the Governments of the world do actually tell the truth.

Oh, I have a feeling that if some politician proclaimed, "The moon landings were faked!", the woos would take it as proof positive :D

Edit - to fix botched attributions...should have tried "preview" :(

JayUtah
2005-Aug-18, 04:23 PM
They will inevitably offer arguments like:

To which we can offer the responses...

Well if the Russians put up reflectors there without landing a human, why couldn't we?

We could. But did we?

We can admit that the technology existed, and we can agree that the Soviets did it and go on to argue that the Apollo reflectors are demonstrably better because they were hand-positioned. But that is not the strongest argument we can make.

This is where the question departs from nuts-and-bolts argumentation and becomes a discussion of what constitutes proof. The conspiracists believe that just by suggesting a hypothetical alternative to some given explanation, they've rendered the explanation suspect or untenable. A moment's thought reveals that this lays in an unjustly heavy burden of proof upon the apologists. Not only must the apologist justify his explanation according to the the available evidence, he must also defend it against purely conjectural notions that may have no evidence whatsoever to suggest they may have happened. If there is no standard of evidence for hypotheses -- such that even speculation is considered a meaningful challenge -- then there is no end to the competition for any hypothesis (no matter how securely established) and then no intellectual progress can ever be made.

Put concretely, if a witness testifies to something, the opposing counsel cannot impeach the testimony simply by saying, "Your honor, this witness may be lying." That's always a possibility, and a witness is not considered authoritative only when it is deemed impossible for him to lie. Suggesting that a witness is lying creates a burden of proof to demonstrate the lie; the suggestion alone is insufficient.

If there are two competing explanations, they must be tested equally against the evidence. You don't dismiss one simply because it is not the only one.

Most pseudoscientists cleverly try to get their opponents to accept a much heavier burden of proof than is appropriate. Even if we believe we can satisfy that burden of proof for one question, we must resist the style of argumentation outright because it may not be possible to satisfy it on some other question. Where the mode of argumentation is wrong, that must be the point of challenge.

Or: it is a trick, the lasers are not really reflecting.

That makes it difficult to fool international researchers. Are they all in on the hoax?

Or: We just happened to discover a reflective patch of moon rock and are now claiming we put it there.

Appeal to magic. That is, the conspiracist simply speculates upon some farfetched notion. Again, this implies that the defender of the common explanation must show not only that it is the most probable explanation, but also that it is the only possible explanation: an outlandish standard of proof.

It doesn't matter, they will always find an objection or make one up.

Exactly. The conspiracists did not arrive at their conclusions by examining the evidence, and so they cannot generally be swayed by a re-examination of it.

die Nullte
2005-Aug-19, 02:09 AM
Are they all in on the hoax?

No, it just means that your "international researchers" are, as a group, easily fooled. This view comes from the idea that scientists and engineers are not really smarter than other people, they're just more practiced at obscuring their lack of real knowledge with insider jargon and circular thinking. Don't laugh. I'm repeatedly encountering this view, either explicitly stated or implied, in another forum on another topic.

Enzp
2005-Aug-19, 06:16 AM
As a conspirator, we would ask not if ALL the scientists were in on it, but how do we know they actually reflected anything off the moon? None of us ever saw it. They probably just claimed it...

ANd on it goes.

montebianco
2005-Aug-19, 12:03 PM
As a conspirator, we would ask not if ALL the scientists were in on it, but how do we know they actually reflected anything off the moon? None of us ever saw it. They probably just claimed it...

ANd on it goes.

Well, possibly, but in this case, they'd still be "in on it."

Extravoice
2005-Aug-19, 02:22 PM
How could it be such an accurate reflection over such a large distance? Off by a tiny fraction of a degree and your radio wave would not be returned to the proper spot.

Peter, I believe that in your original post you meant to refer to the laser reflections that other folks have discussed in detail. However, since you did say RADAR , I feel obliged to mention the Diana project that my Grandfather worked on in the 1940's. They successfully bounced a radar beam off the moon without reflectors. Here is a link with info:

http://www.infoage.org/diana.html

JayUtah
2005-Aug-19, 05:50 PM
Don't laugh. I'm repeatedly encountering this view, either explicitly stated or implied, in another forum on another topic.

Not laughing in the least. The tenet you describe is an oft-encountered doctrine of conspiracism and other forms of pseudoscience.

Maybe there's some projection involved there, since most of what you get from conspiracists is nothing but meaningless jargon and stilted reasoning. But fundamentally, if you subscribe to the notion that pseudoscientists create their own self-centered fantasy worlds in order to compensate for their perceived shortcomings, then it follows that you would have to create villains and charlatans against which you can "fight" and emerge the victor. The villains in the pseudoscientific universe are mainstream scientists.

peter eldergill
2005-Aug-19, 07:13 PM
Peter, I believe that in your original post you meant to refer to the laser reflections that other folks have discussed in detail.

I assumed that it was radio, not laser. I didn't think there were powerful enough lasers for that distance, or maybe the power doesn't have to be that high

Well, I'm here to learn stuff!

Pete

Laser Jock
2005-Aug-19, 07:46 PM
I assumed that it was radio, not laser. I didn't think there were powerful enough lasers for that distance, or maybe the power doesn't have to be that high


Actually the power does have to be very high. By the time the beam distorts as it travels through the atmosphere and expands all the way to the moon, it is several kilometers wide. A tiny fraction of the light actually hits the LRRR and hopefully some of that gets back to the telescope that sent it off. That is why in these experiments they use powerful pulsed lasers that are emit very short pulses (10^-9 to 10^-14 seconds) with very high peak powers. Even so, they only get a handful of photons back with each pulse. Fortunately you can count individual photons so it's a difficult, but not impossible, measurement.

peter eldergill
2005-Aug-20, 05:19 AM
Fortunately you can count individual photons[/i] (italics mine)

Wow, that is absolutely incredible! I am amazed. Is this done with a CCD? I only learned about these once in an astronomy class 10 years ago

Pete