T Nation

Why Won't NASA Show Moon Lander Photos?


#1

Point a telescope at the moon and take pictures of the old moon lander part that stayed behind? The Lunar Rover is also there, as is the flag they planted.

They know the exact coordinates where to point the telescopes. So why not just do it for nostalgia?

It's also interesting that if we're about the repeat the moon landing, as in, doing it again, our preparation time line is as if we're doing it all for the first time.


#2

It’s not a flight from Chicago to L.A. I would hope they take plenty of time preparing for it, considering the dangers involved.

By the way they do point lasers up at the moon that reflect off of the man-made object left there.


#3

[quote]super saiyan wrote:

It’s not a flight from Chicago to L.A. I would hope they take plenty of time preparing for it, considering the dangers involved.

By the way they do point lasers up at the moon that reflect off of the man-made object left there.[/quote]

Mirrors like that can be placed by a simple rocket, no mission is required. Anyway why don’t they just Photo the last landing site? All the eqp is still there.


#4

[quote]Gregus wrote:
super saiyan wrote:

It’s not a flight from Chicago to L.A. I would hope they take plenty of time preparing for it, considering the dangers involved.

By the way they do point lasers up at the moon that reflect off of the man-made object left there.

Mirrors like that can be placed by a simple rocket, no mission is required. Anyway why don’t they just Photo the last landing site? All the eqp is still there.

[/quote]

Did you read the link? It says…

no telescope on Earth or in space has that kind of resolving power. “You can calculate this,” Plait said. “Even with the biggest telescope on Earth, the smallest thing you can see on the surface of moon is something bigger than a house.”

Also, as someone said on another thread - if we faked it, the Russians would have been the first ones to call us on it. They did not want us to get there first and they were tracking the mission the whole time.


#5

I have not run the calculation but I highly doubt that the Hubble Space Telescope lacks the resolving power to pick up the lunar lander first stage at a mere quarter-million miles.

A problem however might well be brightness. The Moon is vastly, vastly, vastly brighter than what the HST is designed for. Like asking an owl to look at the Sun and pick out sunspots.


#6

This link has the calculation:

http://curious.astro.cornell.edu/question.php?number=134

From the link:

Yes, the flag is still on the moon, but you can’t see it using a telescope. I found some statistics on the size of lunar equipment in a Press Kit for the Apollo 16 mission. The flag is 125 cm (4 feet) long, and you would need an optical wavelength telescope around 200 meters (~650 feet) in diameter to see it. The largest optical wavelength telescope that we have now is the Keck Telscope in Hawaii which is 10 meters in diameter. The Hubble Space Telescope is only 2.4 meters in diameter - much too small!

Resolving the larger lunar rover (which has a length of 3.1 meters) would still require a telescope 75 meters in diameter.

Even barely resolving the lunar lander base, which is 9.5 meters across (including landing gear), would require a telescope about 25 meters across. And in reality you would want a couple (or a few) resolution elements across the object so that it’s possible to identify it. (Otherwise it’ll look like a one pixel detection, not an image, and I don’t think people would be convinced by a couple pixels!)

In addition, with a ground based telescope, you have to deal with distortion by the atmosphere as well, so you’ll probably want something considerably larger than 25 meters if you want a good, believable, image of the lander. We don’t have anything that big built yet!

So there’s really no way to image equipment left behind by the astronauts with current telescope technology.

More details for the mathematically inclined: How did I calculate this stuff? Well, here’s the procedure. Let’s take the case of Hubble and find out what the smallest thing it can see on the surface of the Moon is.

  1. Resolution (in radians) = (wavelength)/(telescope diameter) or R= w/D. This is a formula from optics.

  2. So for Hubble we know that the telescope diameter is 2.4 meters (it’s not very big - it had to fit into the Shuttle.) Also, we know that visible wavelength light is in the range 400-700 nanometers. I’ll use 600 nm, because it’s somewhere in the middle and I’ve used it before for this calculation.

  3. If you use all units of meters and do R= (600e-9)/(2.4) = 2.5e-7. Well, that gives us the resolution of Hubble in radians which isn’t too intuitive, but we can convert to meters on the surface of the Moon.

  4. To find the spatial extent that 2.5e-7 radians is at the distance of the moon, set up a triangle between Earth and the Moon, where R is the angle in radians that we calculated, x is the side opposite angle R which corrosponds to the object on the moon, and the adjacent side is the Earth-Moon distance. Then you have Tangent®=x/(distance Moon).

The distance to the moon is 384,400 km. So converting to meters again and plugging in R and d_moon will give you a size in meters of the smallest size thing HST can see.

  1. When you do this you get 96.1 meters (315 feet). The astronauts didn’t leave anything this big! If you look at this HST image of the Moon you can see that they say “Hubble can resolve features as small as 280 feet across.” I think they used 500 nm as their wavelength instead of 600 nm, but it’s the same order of magnitude as what we got here.

So there’s no way HST can see anything humans left behind. HST can do a good job of studying large-scale geology, like craters, which is what the images were of. People and their stuff are just really small on a planetary scale!


#7

[quote]super saiyan wrote:
This link has the calculation:

http://curious.astro.cornell.edu/question.php?number=134

From the link:

Yes, the flag is still on the moon, but you can’t see it using a telescope. I found some statistics on the size of lunar equipment in a Press Kit for the Apollo 16 mission. The flag is 125 cm (4 feet) long, and you would need an optical wavelength telescope around 200 meters (~650 feet) in diameter to see it. The largest optical wavelength telescope that we have now is the Keck Telscope in Hawaii which is 10 meters in diameter. The Hubble Space Telescope is only 2.4 meters in diameter - much too small!

Resolving the larger lunar rover (which has a length of 3.1 meters) would still require a telescope 75 meters in diameter.

Even barely resolving the lunar lander base, which is 9.5 meters across (including landing gear), would require a telescope about 25 meters across. And in reality you would want a couple (or a few) resolution elements across the object so that it’s possible to identify it. (Otherwise it’ll look like a one pixel detection, not an image, and I don’t think people would be convinced by a couple pixels!) In addition, with a ground based telescope, you have to deal with distortion by the atmosphere as well, so you’ll probably want something considerably larger than 25 meters if you want a good, believable, image of the lander. We don’t have anything that big built yet! So there’s really no way to image equipment left behind by the astronauts with current telescope technology.

More details for the mathematically inclined: How did I calculate this stuff? Well, here’s the procedure. Let’s take the case of Hubble and find out what the smallest thing it can see on the surface of the Moon is.

  1. Resolution (in radians) = (wavelength)/(telescope diameter) or R= w/D. This is a formula from optics.

  2. So for Hubble we know that the telescope diameter is 2.4 meters (it’s not very big - it had to fit into the Shuttle.) Also, we know that visible wavelength light is in the range 400-700 nanometers. I’ll use 600 nm, because it’s somewhere in the middle and I’ve used it before for this calculation.

  3. If you use all units of meters and do R= (600e-9)/(2.4) = 2.5e-7. Well, that gives us the resolution of Hubble in radians which isn’t too intuitive, but we can convert to meters on the surface of the Moon.

  4. To find the spatial extent that 2.5e-7 radians is at the distance of the moon, set up a triangle between Earth and the Moon, where R is the angle in radians that we calculated, x is the side opposite angle R which corrosponds to the object on the moon, and the adjacent side is the Earth-Moon distance. Then you have Tangent®=x/(distance Moon). The distance to the moon is 384,400 km. So converting to meters again and plugging in R and d_moon will give you a size in meters of the smallest size thing HST can see.

  5. When you do this you get 96.1 meters (315 feet). The astronauts didn’t leave anything this big! If you look at this HST image of the Moon you can see that they say “Hubble can resolve features as small as 280 feet across.” I think they used 500 nm as their wavelength instead of 600 nm, but it’s the same order of magnitude as what we got here. So there’s no way HST can see anything humans left behind. HST can do a good job of studying large-scale geology, like craters, which is what the images were of. People and their stuff are just really small on a planetary scale! [/quote]

How convenient. We can see distant galaxies far far away and we can’t even try to look at anything as close as the moon. I don’t quite buy it.

As Bill Roberts pointed out, im sure the Hobble could see it, but i don’t think it would take even that.


#8

[quote]super saiyan wrote:
Gregus wrote:
super saiyan wrote:

It’s not a flight from Chicago to L.A. I would hope they take plenty of time preparing for it, considering the dangers involved.

By the way they do point lasers up at the moon that reflect off of the man-made object left there.

Mirrors like that can be placed by a simple rocket, no mission is required. Anyway why don’t they just Photo the last landing site? All the eqp is still there.

Did you read the link? It says…

no telescope on Earth or in space has that kind of resolving power. “You can calculate this,” Plait said. “Even with the biggest telescope on Earth, the smallest thing you can see on the surface of moon is something bigger than a house.”

Also, as someone said on another thread - if we faked it, the Russians would have been the first ones to call us on it. They did not want us to get there first and they were tracking the mission the whole time.[/quote]

I doubt the Russians would have caught on. Their technology was pretty primitive for the time period. They had some early successes but alot of it was luck, if you saw their space program you would know that. So all in all they were not nearly as technically advanced as us. In other words they hardly had the technology to do anything close to monitoring the USA’s actions on the moon. Not by a million.


#9

Didn’t like a week ago NASA publish imagines of the lunar landing equipment taken by an orbiting probe they sent there?

And as for why they can’t just load up a shuttle and go, I would assume that they (1) no longer have working equipment to land on the moon and thus must design and built new equipment that will work with the shuttle, and (2) NASA has said they want to go to different spots on the moon, which will require new recon data.


#10

[quote]Bill Roberts wrote:

A problem however might well be brightness. The Moon is vastly, vastly, vastly brighter than what the HST is designed for. Like asking an owl to look at the Sun and pick out sunspots.

[/quote]

That is a good point and an interesting analogy.


#11

[quote]Gregus wrote:
super saiyan wrote:
This link has the calculation:

http://curious.astro.cornell.edu/question.php?number=134

From the link:

Yes, the flag is still on the moon, but you can’t see it using a telescope. I found some statistics on the size of lunar equipment in a Press Kit for the Apollo 16 mission. The flag is 125 cm (4 feet) long, and you would need an optical wavelength telescope around 200 meters (~650 feet) in diameter to see it. The largest optical wavelength telescope that we have now is the Keck Telscope in Hawaii which is 10 meters in diameter. The Hubble Space Telescope is only 2.4 meters in diameter - much too small!

Resolving the larger lunar rover (which has a length of 3.1 meters) would still require a telescope 75 meters in diameter.

Even barely resolving the lunar lander base, which is 9.5 meters across (including landing gear), would require a telescope about 25 meters across. And in reality you would want a couple (or a few) resolution elements across the object so that it’s possible to identify it. (Otherwise it’ll look like a one pixel detection, not an image, and I don’t think people would be convinced by a couple pixels!) In addition, with a ground based telescope, you have to deal with distortion by the atmosphere as well, so you’ll probably want something considerably larger than 25 meters if you want a good, believable, image of the lander. We don’t have anything that big built yet! So there’s really no way to image equipment left behind by the astronauts with current telescope technology.

More details for the mathematically inclined: How did I calculate this stuff? Well, here’s the procedure. Let’s take the case of Hubble and find out what the smallest thing it can see on the surface of the Moon is.

  1. Resolution (in radians) = (wavelength)/(telescope diameter) or R= w/D. This is a formula from optics.

  2. So for Hubble we know that the telescope diameter is 2.4 meters (it’s not very big - it had to fit into the Shuttle.) Also, we know that visible wavelength light is in the range 400-700 nanometers. I’ll use 600 nm, because it’s somewhere in the middle and I’ve used it before for this calculation.

  3. If you use all units of meters and do R= (600e-9)/(2.4) = 2.5e-7. Well, that gives us the resolution of Hubble in radians which isn’t too intuitive, but we can convert to meters on the surface of the Moon.

  4. To find the spatial extent that 2.5e-7 radians is at the distance of the moon, set up a triangle between Earth and the Moon, where R is the angle in radians that we calculated, x is the side opposite angle R which corrosponds to the object on the moon, and the adjacent side is the Earth-Moon distance. Then you have Tangent®=x/(distance Moon). The distance to the moon is 384,400 km. So converting to meters again and plugging in R and d_moon will give you a size in meters of the smallest size thing HST can see.

  5. When you do this you get 96.1 meters (315 feet). The astronauts didn’t leave anything this big! If you look at this HST image of the Moon you can see that they say “Hubble can resolve features as small as 280 feet across.” I think they used 500 nm as their wavelength instead of 600 nm, but it’s the same order of magnitude as what we got here. So there’s no way HST can see anything humans left behind. HST can do a good job of studying large-scale geology, like craters, which is what the images were of. People and their stuff are just really small on a planetary scale!

How convenient. We can see distant galaxies far far away and we can’t even try to look at anything as close as the moon. I don’t quite buy it.

As Bill Roberts pointed out, im sure the Hobble could see it, but i don’t think it would take even that. [/quote]

I don’t even know what to say to that. The sheer stupidity involved in believing a T-Nation forum member over actual astronomers providing provable mathematical calculations is one of the most ridiculous things I’ve ever tried to comprehend.


#12

My mistake, I should have done the calculation or found a source that did (the first link only asserted it) rather than using my (wrong) opinion of the resolution of the HST.

As a completely separate point, that’s really not just what I’d had it cracked up to be. For illustration, let’s take that 384,400 km and convert it to 384 km, which is a fairly modest orbital height above the Earth. (Not as low as a spy satellite can be, though.)

315 feet then converts to 315/1000ths of a foot, or basically about 4 inches not counting effect of the Earth’s atmosphere.

Either the claims of what spy satellites can do are lies, or Hubble is no or little better than them, whereas I had wrongly figured that, if not for the Earth’s atmosphere, at such a distance it would surpass the spy satellites for resolution. It cost a ton more anyway and has a bigger mirror so theoretically it should.


#13

[quote]Gregus wrote:

How convenient. We can see distant galaxies far far away and we can’t even try to look at anything as close as the moon. I don’t quite buy it.

As Bill Roberts pointed out, im sure the Hobble could see it, but i don’t think it would take even that. [/quote]

No offense, but what the fuck do you know about optics and telescopes? This isn’t something that “you just don’t buy”–the math is in front of you. Unless you’re an astrophysicist with lots of knowledge and experience on these things, what you “buy” doesn’t matter.

This would be like your average John Doe telling an electrical engineer, “Nope, I just don’t buy it. There’s just no way those electrons can break the conservation of energy like that”.


#14

[quote]super saiyan wrote:

I don’t even know what to say to that. The sheer stupidity involved in believing a T-Nation forum member over actual astronomers providing provable mathematical calculations is one of the most ridiculous things I’ve ever tried to comprehend.[/quote]

Kinda like the debates over global warming and evolution that pop up every other month…


#15

[quote]stokedporcupine8 wrote:
Gregus wrote:

How convenient. We can see distant galaxies far far away and we can’t even try to look at anything as close as the moon. I don’t quite buy it.

As Bill Roberts pointed out, im sure the Hobble could see it, but i don’t think it would take even that.

No offense, but what the fuck do you know about optics and telescopes? This isn’t something that “you just don’t buy”–the math is in front of you. Unless you’re an astrophysicist with lots of knowledge and experience on these things, what you “buy” doesn’t matter. This would be like your average John Doe telling an electrical engineer, “Nope, I just don’t buy it. There’s just no way those electrons can break the conservation of energy like that”. [/quote]

That is I think unfair to Gregus.

The calculation was NOT (so far as I know) presented to him at the time of his post. Even if it may look that way it may not be the case.

The originally provided post did not provide a calculation for the HST or any claim of a calculation for the HST. It only made an assertion but then went further only for Earth based telescopes.

Extreme resolution for the HST has long been reported. It was reasonable, given that the first link did not go into the issue of the HST at all other than to make an assertion, for Gregus to not consider that a proven matter.

While I haven’t gone back and checked, I didn’t have the impression that the original link was written by a scientist, so your claim that he was arguing against a scientist in his specialty may be quite wrong. (Most science writers for magazines, newspapers, and the like are not scientists and not so expert in what they write.)

As for myself, I was just flat mistaken. But not because I was disagreeing or thought I was disagreeing with a scientist expert in the question, but because it seemed to me that a science writer had made a mere assertion and had only backed up the Earth half of it.


#16

The “About Us” link on the site would have told him who provided the information in the link.

“Ask an Astronomer is run by volunteers in the Astronomy Department at Cornell University. There are several astronomers involved in maintaining this site and answering the questions sent in.”

Also, it’s not like these are the only people providing calculations to prove the point. A little research on his own could confirm that. I really don’t think Gregus would change his mind no matter how much math and science you throw in front of him.


#17

Well, why not let him speak for himself on that.

Myself, it was an uncharacteristic error. I ordinarily do calculate such things but failed in this instance. :frowning:

When someone puts up a link, it’s unreasonable to expect that each reader will follow up BEYOND what the link itself says. It is only reasonable to expect them to read the link.

Which says only, besides stating the myth, "The fact of the matter is … no telescope on Earth or in space has that kind of resolving power. ‘You can calculate this,’ Plait said. “Even with the biggest telescope on Earth, the smallest thing you can see on the surface of moon is something bigger than a house.”

That doesn’t tell me who Platt is. It doesn’t say anything about how you could calculate it for the HST. It only makes an assertion regarding space telescopes. Not such a good job, really, of proving a point is it? It sure as hell could have stated, regarding the HST, what size object it could resolve on the Moon. The reader may not be aware, though I should have figured myself, that despite the Earth’s atmosphere actually it is less resolution (at least for the modern telescopes that mimic much larger size than any one individual mirror that they have.)


#18

I don’t know that the comparison between telescopes and things like spy satellites really hold up. They really aren’t that similar. I really don’t know a ton about optics, but the designed focal length is entirely different. Spy satellites are designed specifically to view things within a handful of miles. Telescopes are designed to focus on things light years away.

I do not think you could turn a spy satellite around and get quality images of the stars or turn the Hubble around and get good images of the ground.

Go and get a home telescope and try and look as something across the room. Go get binoculars and try to look at a microscope slide. Go get a microscope and try and spy on your neighbor’s house. None of that makes any sense.

I don’t think it is that improbable that devices built to focus on things of a massive scale
hundreds of millions of miles away would suck at detecting a rover on something as close as the moon.

The seemingly natural comparison of things that optically enlarge images is really a lot more complicated.


#19

[quote]Bill Roberts wrote:
stokedporcupine8 wrote:
Gregus wrote:

How convenient. We can see distant galaxies far far away and we can’t even try to look at anything as close as the moon. I don’t quite buy it.

As Bill Roberts pointed out, im sure the Hobble could see it, but i don’t think it would take even that.

No offense, but what the fuck do you know about optics and telescopes? This isn’t something that “you just don’t buy”–the math is in front of you. Unless you’re an astrophysicist with lots of knowledge and experience on these things, what you “buy” doesn’t matter. This would be like your average John Doe telling an electrical engineer, “Nope, I just don’t buy it. There’s just no way those electrons can break the conservation of energy like that”.

That is I think unfair to Gregus.

The calculation was NOT (so far as I know) presented to him at the time of his post. Even if it may look that way it may not be the case.

The originally provided post did not provide a calculation for the HST or any claim of a calculation for the HST. It only made an assertion but then went further only for Earth based telescopes.

Extreme resolution for the HST has long been reported. It was reasonable, given that the first link did not go into the issue of the HST at all other than to make an assertion, for Gregus to not consider that a proven matter.

While I haven’t gone back and checked, I didn’t have the impression that the original link was written by a scientist, so your claim that he was arguing against a scientist in his specialty may be quite wrong. (Most science writers for magazines, newspapers, and the like are not scientists and not so expert in what they write.)

As for myself, I was just flat mistaken. But not because I was disagreeing or thought I was disagreeing with a scientist expert in the question, but because it seemed to me that a science writer had made a mere assertion and had only backed up the Earth half of it.[/quote]

My point, which was what does he knows about optics and telescopes, would hold up even if the calculation wasn’t there. Gregus asserted something to the effect of “Well, if we really landed on the moon we should be able to point HST there and look…”. The burden of proof is on him. He needs to back up his uneducated conjecture on just what the HST can and can’t do. Arguing intuitively that “well, since it can see galaxies, it should be able to see stuff on the moon” is silly. There could be dozens of reasons that someone not familiar with optics or astrophysics wouldn’t know that would allow the HST to see the former but not the latter.

The spirit of my post though was really in response to the general anti-science attitude on this forum. It seems that many people here think their soooo smart, and know soooo much about science without ever having seriously studied any science at all. The general idea that one can just apply intuitive common sense arguments and that there is no need to look into the deeper work that scientists have done is a stupid idea.


#20

[quote]Bill Roberts wrote:
My mistake, I should have done the calculation or found a source that did (the first link only asserted it) rather than using my (wrong) opinion of the resolution of the HST.

As a completely separate point, that’s really not just what I’d had it cracked up to be. For illustration, let’s take that 384,400 km and convert it to 384 km, which is a fairly modest orbital height above the Earth. (Not as low as a spy satellite can be, though.)

315 feet then converts to 315/1000ths of a foot, or basically about 4 inches not counting effect of the Earth’s atmosphere.

Either the claims of what spy satellites can do are lies, or Hubble is no or little better than them, whereas I had wrongly figured that, if not for the Earth’s atmosphere, at such a distance it would surpass the spy satellites for resolution. It cost a ton more anyway and has a bigger mirror so theoretically it should.

[/quote]

You do realize that this same idea can be applied in reserve to Hubble?

Consider:

The following galaxy imaged by Hubble is about 25 million light years away.

http://images.google.com/imgres?imgurl=http://www.nasa.gov/images/content/143744main_hubble_spiral_2006.jpg&imgrefurl=http://www.nasa.gov/mission_pages/hubble/science/hst_spiral_m10.html&usg=__NGLC57R4THXnEHSvdxK7TxAwgMQ=&h=391&w=500&sz=43&hl=en&start=6&um=1&tbnid=P_0Nu03Bwo28CM:&tbnh=102&tbnw=130&prev=/images%3Fq%3Dgalaxies%2Bhubble%26hl%3Den%26safe%3Doff%26client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official%26sa%3DX%26um%3D1

You can look the conversion up, but 25 million light years is about 2.365e23 meters. Given R=2.5e-7, that means that at that distance, Hubble can pick up objects that are about 5.9125e16 meters across. Converting again back to light years, 5.9125e16 meters is about 6.25 light years. That means, very roughly, that Hubble is able to pick up objects that are 6 light years across at 25 million light years away. Given that in the image of Messier 101 the biggest objects we can make out are clumps of stars, I’d say those calculations sound about right.

The point is that a resolution of 2.5e-7 radians is apparently sufficient to produce the images of galaxies that Hubble does. Whether or not earth spy satellites have a similar resolution doesn’t matter–neither these satellites nor Hubble can pick up small objects on the moon, nor does Hubble require a resolution any greater then that to image the galaxies it does.

In the end I’m sure that there are MANY other difference between Hubble and spy satellites that justify the difference in cost and explain their different abilities, but those are all irrelevant for the point at hand.