Because you don't seem to be able to accept a simple answer to the questions and ideas you pose, it becomes increasingly necessary to point out how and why things work and don't work. I'm only pointing out commonly available knowledge that anyone who did a bit of research could find in a few minutes on the internet. There is nothing in the terms of service requiring facts to be dumbed down to the point they don't mean anything. This has nothing to do with my ego; I've just learned some stuff over the years. There are plenty of other people that use these boards that can understand what I'm talking about and there are some, including someone who lives quite near me, who can and do go into far more excruciating detail than I do. I try to explain things I understand as simply as possible so the most number of readers can follow it. It isn't nitpicking to give broad, general discussions of engineering and Physics principles. I live around and hang out with people who know these things and more. We carry on much more involved and detailed discussions all the time and try to learn new things from each other because we all have different realms of experience and expertise. If you are uninterested in learning something, that's your choice.
Originally posted by dfez: Because you don't seem to be able to accept a simple answer to the questions and ideas you pose, it becomes increasingly necessary to point out how and why things work and don't work. I'm only pointing out commonly available knowledge that anyone who did a bit of research could find in a few minutes on the internet. There is nothing in the terms of service requiring facts to be dumbed down to the point they don't mean anything. This has nothing to do with my ego; I've just learned some stuff over the years. There are plenty of other people that use these boards that can understand what I'm talking about and there are some, including someone who lives quite near me, who can and do go into far more excruciating detail than I do. I try to explain things I understand as simply as possible so the most number of readers can follow it. It isn't nitpicking to give broad, general discussions of engineering and Physics principles. I live around and hang out with people who know these things and more. We carry on much more involved and detailed discussions all the time and try to learn new things from each other because we all have different realms of experience and expertise. If you are uninterested in learning something, that's your choice.
OK, I have seen this topic climb back to the top a few times now, and since it has reached 7 pages long, (and I have read all 7 pages) it's time I chimed in...
First off, in the first few pages, I see reference to using different types of technology to find the flagpole, and later I see reference to finding the actual landing sites. I believe what we are missing is the fact that Earth has left approximately 170,000 KG's of "stuff" behind on the moon. That's One-Hundred and Seventy THOUSAND KILO-GRAMS! Why are we wasting time looking for flagpoles and landing sites?
It all started in 1959, when the Soviets left the Luna 2, weighing in at 390 KG. The U.S. quickly followed in 1962, with the Ranger 4, at 331 KG. In fact,before we ever set foot on the moon, there was 30 different types of satellite probes already on the moon, with the heaviest weighing in at 2,718 KG's. After the landing, there have been an additional 36 large items, including 5 3rd stages of rockets, with the largest weighing in at 14,036 KG's, yet we are still talking about looking for a flagpole or a landing area?
The only objects left there, that we still use today are 3 different retroreflectors for the Lunar Laser Ranging Experiment. These reflectors use lasers and the speed of light to determine the distance between the Earth and the moon.
On another note, the Lunar Rover was left on the moon in 1971. The Lunar Rover weighed 462 KG's. Since there is nothing on the moon that can rust or deteriorate the Lunar Rover, I wonder if someone couldn't take a few batteries to the moon and power it up...
But, my overall point is this: If there are that many man-made objects still on the moon, why are we looking for a flagpole or a landing site? And I don't know much about telescopes or laser detecting devices, but I'm sure ordinary citizens could detect some of these larger objects.
There is a couple things that have probably deteriorated the Lunar Rovers; 35 years of exposure to direct Solar radiation has probably deteriorate such things as electronic controllers, radios, and any plastic parts that are exposed. The Surveyor Lander parts brought back by Apollo 12 showed quite a bit of fading and pitting after just 32 months. There is also a continuous b0mbardment by micro-meteorites to consider. Finally, there's a man-made problem that's only now being considered; the problem of high velocity particles of Regolith being blasted long distances by rocket engines. The exhaust velocities of rocket engines can pick up the Lunar Dust and throw it very long distances at large fractions of Lunar Orbital velocity. When the Apollo 12 Astronauts brought back the camera from Surveyor, it was found that the descent engine had thrown the dust so violently that it was inside the lens of the camera and the craft landed more than 200 yards from Surveyor. This sounds sort of strange, but, since there is no atmosphere to slow down the dust particles, there is some concern that landings almost anywhere on the Moon could contaminate other sites. The larger objects you describe probably impacted the Moon at at least 1500 mph or more and probably became confetti. It might be possible to find new impact craters they formed though. The Lunar CTs are demanding proof that we landed men on the Moon, so it wouldn't be enough to merely show that we've crashed things there because they mostly seem to allow that we could have done that. Again, neither the largest Earth Based telescopes or Hubble have near the angular resolution to see any of these objects at 240,000 miles distance. It's just simply. out of the range of any professional or amateur instruments. The Lunar Rovers were smaller than the LEM Descent Stages left behind, so it wouldn't help trying to see them. I suspect that, when and if we return to the Moon, major efforts will be made to preserve the Apollo sites as historical monuments and not much of them will be tampered with, but there might be some investigation to determine how materials fared over the years. It might be interesting to try to power up a Rover though just to see what happens? Basic Science, you know.
As far as I know, the lunar rover contained no plastic or rubber. Even the tires were made of a metal mesh, simulating an inflated rubber tire. I bet with a couple of fresh batteries, the rover would fire right up.
Originally posted by HUDMAN: As far as I know, the lunar rover contained no plastic or rubber. Even the tires were made of a metal mesh, simulating an inflated rubber tire. I bet with a couple of fresh batteries, the rover would fire right up.
There was lots of plastic including the seats and seatbelts. I would be more concerned about the insulation in the electronics. There was a lot of wiring in the motor controllers, radios, TV camera, and dish antenna pointing mechanism. Many of the polymers, plastics, and rubbers used on the Apollos are crumbling into dust; even in controlled atmosphere in the NASA archives. It seems unlikely they would hold up very well on the Lunar Surface.
Good point dfez, I guess I was referring to the larger components and not thinking of the things that actually made it go, like electrical wiring and insulation.
On another note, there are 3 lunar rovers that were left on the moon from Apollos 15, 16, & 17.
If they were able to fire up with fresh batteries, why did NASA send up additional rovers if they could have used existing ones? Unless, that is, they wanted to explore other parts of the moon, which is probably the correct answer.
Originally posted by HUDMAN: Good point dfez, I guess I was referring to the larger components and not thinking of the things that actually made it go, like electrical wiring and insulation.
On another note, there are 3 lunar rovers that were left on the moon from Apollos 15, 16, & 17.
If they were able to fire up with fresh batteries, why did NASA send up additional rovers if they could have used existing ones? Unless, that is, they wanted to explore other parts of the moon, which is probably the correct answer.
Yeah , the landing sites were way too far apart for the range of the Rover's batteries to reach the others. The Rovers had nonrechargeable batteries and were only intended to run a distance away from the landing sites that was less than the Astronauts could walk back to the LEM with the consumables they had if the Rover broke down. You also need to consider that the Rovers have now been subjected to more than 400 cycles of being baked for 2 weeks at a time in temperatures in excess of 250 -300 degrees and then frozen for 2 weeks at -180 degrees. That kind of heat and cold soaks are really detrimental to complicated electromechanical devices that weren't really meant to endure them. The projected surface life of the Rovers was less than a week. All that doesn't take into account the persistent, unshielded radiation from the Sun and the continuous b0mbardment by micrometeorites. They are working on new Rover designs with extended staying power, longer range, and enclosed cabins for the proposed Moon missions, but the old ones are probably toast.
Originally posted by coranthulle: I keep seeing a common statement that no telescope on earth or in orbit has the resolution to see objects on the moon.
I was wondering where this notion came from as well. The Hubble's optics could resolve a picture of the landing sites but it is programed never to point at the moon. The reason is the CCD's inside Hubble are made for looking at DISTANT and VERY DIM objects in deep space. The moon is way too bright! If the Hubble even accidently swept past the moon on it's way to look at something else it would burn out the detectors resulting in a loss of mission for the telescope.
As for our spy satellites... they are made to look at something bright but if the government took a picture of the rovers on the moon with one of the spy telescopes it would reveal just how good those telescopes are. If they can resolve the rovers which are much farther away than the surface of the earth then everyone will know that they can see A LOT when they look down at us!
Also, if we really did fake the moon shot then the Soviets would have called us out on it back then and they would have finished going there rather than giving up!
I was wondering where this notion came from as well.
Basic optics... as explained repeatedly in this and other threads.
quote:
The Hubble's optics could resolve a picture of the landing sites
No, it can't.
quote:
The reason is the CCD's inside Hubble are made for looking at DISTANT and VERY DIM objects in deep space. The moon is way too bright! If the Hubble even accidently swept past the moon on it's way to look at something else it would burn out the detectors resulting in a loss of mission for the telescope.
The moon does not have phases anymore?
quote:
As for our spy satellites... they are made to look at something bright but if the government took a picture of the rovers on the moon with one of the spy telescopes it would reveal just how good those telescopes are. If they can resolve the rovers which are much farther away than the surface of the earth then everyone will know that they can see A LOT when they look down at us!
Is this meant to be serious?? What kind of resolution at 375,000 km do you think it would have if it's 6" at 100km? Just under 2000 *feet* perhaps?
Hm, to be fair, roofing and dfez are factually correct, but IMHO being a bit hardcore in the presentation (I know it's trying, but please be patient). After all, some of these posters are probably on the young side and even 'basic' optics is part of college level physics At least they're agreeing with the basic premise of this thread: moon landing = real. Now, if they troll us about US fakery and moon sets in Arizona, please show no mercy
Yes, but to be fair badgolf, there is already 7 pages in this thread alone, along with the other threads, that deal with the resolution issues with visible light and radio waves.
As wjpskeptic's Hubble moon shots link shows, the Hubble can, in fact, image the moon -- just not the landing sites.
Coming in without reading the thread, and then making false claims isn't really furthering the discussion.
Yes, I could have not responded at all, or could have responded in a different way, but the post also could have asked "Can/can't..." about equipment abilities instead of making (incorrect) statements with an apparent air of authority. And someone else reading through the thread needs to know the statements are incorrect, or they will take them as fact.
Oh, don't get me wrong, I value the corrections roofing [even when I'm the one being corrected -What's a POAT ]. I don't defend lazy thinking or inattentive posting; I get what you're saying exactly. It's also not fair that you and dfez are stuck trying to make up for what someone's science teacher wouldn't or couldn't teach. I don't envy trying to condense 2 semesters of physics on a message board.
Still, however tempted we are to lose patience, I see the posters in question as allies if not friends: impulsive, boastful, and often misguided (yikes), but basically pro-science allies all the same. Maybe I'm a soft touch, but it seems better to coax them back even part way to the side of rational thought than be super strict and our own worst enemy. That's just my take on it. So if I left my wallet at Mall of the Moon ...
Originally posted by coranthulle: I keep seeing a common statement that no telescope on earth or in orbit has the resolution to see objects on the moon.
I was wondering where this notion came from as well. The Hubble's optics could resolve a picture of the landing sites but it is programed never to point at the moon. The reason is the CCD's inside Hubble are made for looking at DISTANT and VERY DIM objects in deep space. The moon is way too bright! If the Hubble even accidently swept past the moon on it's way to look at something else it would burn out the detectors resulting in a loss of mission for the telescope.
As for our spy satellites... they are made to look at something bright but if the government took a picture of the rovers on the moon with one of the spy telescopes it would reveal just how good those telescopes are. If they can resolve the rovers which are much farther away than the surface of the earth then everyone will know that they can see A LOT when they look down at us!
Also, if we really did fake the moon shot then the Soviets would have called us out on it back then and they would have finished going there rather than giving up!
As was pointed out, the Hubble is perfectly capable of taking pictures of the Moon, but there is an important difference between pointing a telescope or spy satellite at an object and being able to see it. This is the resolution factor we are talking about. Unlike what you see in the entertainment world, optics are not capable of magnifying objects infinitely. You can't keep "Zooming" in on things that are very small or very far away past a certain point; all you end up doing is magnifying a featureless blur. The very best optical systems are said to be Diffraction Limited. This is the limit at which the optical system can distinguish one object from another and is, at best, set by light scattering off the parts of the optical tube assembly and the optical elements themselves. No lens or mirror system is optically perfect and small, and I mean VERY small, defects set the limits of performance. These deviations are measured in tiny fractions if a single wavelength of light. Decent amateur telescopes are figured to an accuracy of 1/8th wavelength of visible light. The primary of the HST was one of the finest optical surfaces ever made; it was finished to 1/92nd of a wave of visible light. Unfortunately, due to an instrument error , that precise shape was not the right one and it required the optical fix that was done to save the mission. One of the great ironies of Hubble is that, after all the millions spent shaping and finishing and testing the mirror, anyone with a cheap, simple tester called a Ronchi Grating could have stood in front of the mirror and instantly seen what was wrong with it, but no one ever did. As for the resolution of spy satellites, they aren't that much of a secret to people who understand optics. Several of our largest optical satellites were very similar in basic design to the Hubble and are limited in performance by the same basic factors as well as the effects of looking down through the atmosphere. Optical performance is limited by it not being magic. Roof, the Hubble has several different imaging systems, but they are all able to survive exposure to the Earth or the Moon; there was just too much chance of that happening during slueing. The detectors could oversaturate and go blank, but they should survive. Still , it's good practice not to point at those objects. The only real danger is pointing at the Sun. I have to say, when I joined the board, I sure never imagined how much time and effort would be involved in explaining and defending so much basic science and history. Nothing I post is very exotic or esoteric knowledge and is readily available to anyone with a Search Engine. It takes far less effort to know these things today in the era of the Net, than it did to actually study them in college. It's kind of a sad commentary on today's education.
I was wondering where this notion came from as well. The Hubble's optics could resolve a picture of the landing sites but it is programed never to point at the moon
Why use hubble? The tech came after Apollo. If a Conspiracy Nuts won't accept the Apollo Missions...why would they believe in the capabilities of HUBBLE? I suppose HUBBLE is a myth also.
Still, however tempted we are to lose patience, I see the posters in question as allies if not friends: impulsive, boastful, and often misguided (yikes), but basically pro-science allies all the same. Maybe I'm a soft touch, but it seems better to coax them back even part way to the side of rational thought than be super strict and our own worst enemy.
Thanks again badgolf for summing up again. I now see how frustrating it can be for dfez to keep ploughing over the same ground. Some of the later replies almost mimicked my 1st one hehe. Hats of to dfez and the others for keeping the wild imaginations in some kind of order. Just keep cutting and pasting us straight thanks. If I'm about I'll try and head them of at the pass for you in the future. It was probably unbridled imaginations like ours that thought of the Wheel, but the dfez's of the day that actually made it. Somewhere in the middle and the CT's will have to suck it back.
Considering now my more realistic outlook and the earlier posts, one that radar is much like any other radiation, just invisible as I think most is. I still am not satisfied that radar is an entirely exhausted thread. My reasonings follow. Radar, as far as I know, is normally sprayed about by the emitter in a broad moving beam, can it be concentrated as with a laser? Maybe with a much longer wavelength than used here on earth. Also I'm sure the software that goes with radar is now quite fancy, disseminating ground interferance and the like. Can it tell what type of craft, without a transponder signal for identification? With a directed radio beam and a few sensitive radio telescopes to triangulate return signals, what do you reckon? Digital picture enhancement and the above maybe we could see a bit, even something blurry? Maybe the spectrum of the return signals could be analysed to show the unnattural concentrations of man made metals? Glad I came here. Where else could I prattle on like this
By the way how do the lunar laser experiments actually find the small reflector on the moons surface. Do they just move the beam about until its found? Pretty hard to do considering what dfez says about how fast the moon is moving.
This message has been edited. Last edited by: mod_ivy,
Still, however tempted we are to lose patience, I see the posters in question as allies if not friends: impulsive, boastful, and often misguided (yikes), but basically pro-science allies all the same. Maybe I'm a soft touch, but it seems better to coax them back even part way to the side of rational thought than be super strict and our own worst enemy.
Thanks for summing up again badgolf. I can now see how frustrating it must be dfez. Keep up the good work. Thanks too dfez for keeping our wild imaginations firmly on this planet. It was probably unbridled imaginers like us that invented the wheel, but the dfez's of world that built it.
I still think, the radar and laser threads have not yet been entirely exhausted. Radar is usually sprayed about in a broad and moving beam. Can it not be concentrated into a beam, as with lasers? Maybe with a much longer wavelength than is used here on earth. Because it would be directional, and not cook humans nearby, very high power could be used. Then a few sensitive radio telescopes could be used to triangulate the signal. Or spectrally analyse the signal to sense unnaturally high concentrations of manmade metals. Radar software would be pretty fancy nowadays and as here on earth disseminate between ground signals and other interferance. Digital picture enhancement could help to get maybe even a blurry image. Well?
Also, how do you, with a laser, find the reflectors on the mo
At least they're agreeing with the basic premise of this thread: moon landing = real. Now, if they troll us about US fakery and moon sets in Arizona, please show no mercy 
