Out of interest? Hoax claims out and about.

[gwiz]

I think he might be getting confused between Laser and Radar (I have already seen that he doesn't understand Radar from discussions I have had with him about tracking spacecraft on orbit)

No, it was in 1962, here's a link that mentions it:
http://web.mit.edu/newsoffice/1996/timeline-1030.html

The difference is that the retroreflectors give a nice sharp return pulse from a single point, while the lunar surface gives a blurred pulse from a broad area.

[gillianren]

I just finished Among the Truthers and this is a point the author also makes: conspiracists come in all kinds, and about the only thing you can say about them in general is that belief in one conspiracy theory is strongly correlated with belief in another (or many).

Though I found it interesting that Apollo is never mentioned in that book.  To me, it was an additional piece of evidence that Moon Hoax belief is declining.

[ka9q]

Both laser and radar were bounced off the moon pre-Apollo. (Radio hams still do it regularly with radio as a sort of ultimate because-it's-there challenge. It's called EME or Earth-Moon-Earth or simply "moonbounce".)

The laser used off the natural surface emitted much higher pulse energies and much longer pulses than those used with the Apollo and Lunokhod retroreflectors, and their receive signal-to-noise ratios were much worse. Even if short pulse lasers could have been built with sufficient energy, the multipath would smear the return pulses over microseconds, rendering them useless for the kind of precise measurements needed to test relativity, the constancy of G, the evolution of the moon's orbit, the earth's polar wobble, and the many other scientific applications based on measurements with centimeter (or better) accuracy of the earth-moon distance.

This is precisely why the lunar retroreflectors were proposed, and why they were considered so scientifically valuable that one flew on the very first Apollo landing mission, one that the powers-that-be wanted kept as simple as possible.

[ka9q]

Though I found it interesting that Apollo is never mentioned in that book.  To me, it was an additional piece of evidence that Moon Hoax belief is declining.

This came up in the NPR interview with the author, and your guess is correct: he said he had difficulty finding enough who thought Apollo was a hoax to provide a representative sample. I think he was also mostly interested in 9/11 conspiracy theories since they are among the most offensive and outrageous of the modern theories. (As much of an Apollo fan as I am, I have to agree it's even more offensive than claiming Apollo was a hoax.)

You get a sense of hopelessness reading most of the book, the feeling that the human race is going nuts and there's nothing we can do about it. But then he actually makes some viable and thoughtful suggestions. His best was to teach about conspiracy theories in the first year of college, before most students have a chance to get sucked in by them. He specifically recommends teaching about The Protocols Of The Elders Of Zion, both because of its extreme historical significance and because literally no one in academia today will still defend them as legitimate.

I guess it's like how no one objects to teaching Greco-Roman mythology (or naming space programs after its gods) because no one still actually believes that stuff.

[ka9q]

The difference is that the retroreflectors give a nice sharp return pulse from a single point, while the lunar surface gives a blurred pulse from a broad area.

Exactly. Even the largest telescopes will still illuminate an area on Luna several km across; the atmosphere tends to decollimate the beam. As long as the return comes from an area that large, it will necessarily be spread out in time by surface curvature even if it were absolutely smooth. The return must come from a small reflector to keep the pulse width small.

As small as the LRRRs are, the returns are still significantly broadened by the finite size of the reflectors and the moon's libration. They were manually aligned quite well using a sundial and bubble level, but because they do not actively track the earth as it moves a few degrees every month in the lunar sky most of the time the array isn't exactly normal to the earth. One part of the array is closer to the earth than another, and that spreads out the return pulse.

Because radio signals have a much longer wavelength than light, and because amateur radio antennas (even big ones) are relatively small, they tend to illuminate the entire lunar disk (and more). Moonbounce operators are used to working with extreme multipath fading, and the design of digital modulation methods for the EME channel has been very challenging. I'm proud of the fact that a ham friend and I published a paper in 1995 with some ideas that another ham picked up, implemented and made work with much smaller antennas and less power than had ever been used in ham EME. And that ham is a Nobel laureate in physics...kinda neat.

[Trebor]

Phil Webb did a very good detailed examination of the laser ranging experiments here :

and

[Peter B]

But then he actually makes some viable and thoughtful suggestions. His best was to teach about conspiracy theories in the first year of college, before most students have a chance to get sucked in by them. He specifically recommends teaching about The Protocols Of The Elders Of Zion, both because of its extreme historical significance and because literally no one in academia today will still defend them as legitimate.

You mean like this course: http://www3.griffith.edu.au/03/STIP4/app?page=CourseEntry&service=external&sp=S2401BPS&sp=S3121&sp=SUGRD&sp=SNA&sp=SP&sp=SNA&sp=l0&sp=SStipHome&sp=SCourse+search&sp=3&sp=SKeyword&sp=T&state:CourseList=BrO0ABXcaAAAAAgAAE3RvdGFsTWF0Y2hlZENvdXJzZXNzcgARamF2YS5sYW5nLkludGVnZXIS4qCk94GHOAIAAUkABXZhbHVleHIAEGphdmEubGFuZy5OdW1iZXKGrJUdC5TgiwIAAHhwAAAAAXcRAAAOc3RhcnRQYWdlSW5kZXhzcQB%2BAAAAAAAA

In case the link doesn't work, it's Griffith University's Skepticism, Science and the Paranormal unit.

Course overview; definition of terms. Approaches to the paranormal and other belief systems. The nature and position of science: intellectual and social aspects. The nature and position of the paranormal: different types of paranormal claims. Skepticism and ways of investigating the paranormal. Paranormalism, skepticism and the media.

[ka9q]

Yeah, but it's in Australia. Offer a course like that in the USA and you'd have an angry mob of fundamentalists outside the adminstration building.

[JayUtah]

The laser used off the natural surface emitted much higher pulse energies and much longer pulses than those used with the Apollo and Lunokhod retroreflectors, and their receive signal-to-noise ratios were much worse.

Indeed, if you understand the science you realize why such early endeavors were useless as ranging exercises.  Hoax believers don't understand the science.  In their simplistic worldview, "But you can bounce a laser off the bare lunar surface," is sufficient to put a pseudo-intellectual veneer over the supposition that there are no artificial retroreflectors on the Moon.

The question in terms of debate is whether to go down the rathole.  Part of it depends on why you're debating.  The compliments I get most frequently are, "I learn so much from your site and your debates."  And that's laudable.  But not everyone wants a science lesson; they just want to know whether smart people put any stock in the hoax theories.  Sometimes the sufficient answer is, "No, you can't actually range the Moon with a laser unless there's a special mirror."  You don't have to go into multipass fading, pulse length, atmospheric scatter, or any of the very real details in which the devil of laser rangefinding lies.

If you're sparring with hoax believers just for fun, then there is a rhetorical aspect you need to consider.  You always want to the truth to come from you, not from your opponent.  The hoax claimant gets a rhetorical boost when he says, "The Apollo defenders didn't tell you that lasers were bounced off the Moon before Apollo."  You're immediately put on the defensive, and that's when the true-but-confusing quantitative arguments fall the most flat.  To the untrained ear they really do come off sounding like techno-babble backpedaling, even though it's the truth.  Winning a debate is about being logical and truthful, but also knowing how best to present the truth.

[ka9q]

Indeed, if you understand the science you realize why such early endeavors were useless as ranging exercises.

Not useless, just not accurate enough to do all the interesting things that are now being done with the LRRR data.

Hoax believers don't understand the science.

Tell me something I don't know!

In their simplistic worldview, "But you can bounce a laser off the bare lunar surface," is sufficient to put a pseudo-intellectual veneer over the supposition that there are no artificial retroreflectors on the Moon.

Right. I've tried to ask why, if they're only showing they can get a reflection from the moon, they keep doing it over and over. The point is to make high accuracy range measurements over a long period of time for numerous scientific tests. "Accuracy" is a quantitative term, so it's hard to avoid giving at least some numbers. And whether one laser or another laser setup can get its reflection off the moon is a quantitative question, so the fact that one can doesn't mean that all of them can, regardless of design.

White's claim that the demonstration at Apache Point didn't prove anything is tantamount to accusing either the Mythbusters or the observatory staff of deliberate lying or falsification of data. And it's very hard to argue with someone whose every answer to a piece of evidence is "they're lying". (Hunchbacked, on the other hand, has become so utterly delusional that he now claims that the various alleged LRRR sites are simply natural features that have somehow fooled the various observatories. It's become nearly impossible to believe this man's assertion that he has an engineering degree.)

Winning a debate is about being logical and truthful, but also knowing how best to present the truth.

Very true.