Any maximum quoted range for these things is probably based on a reading device intended for commercial use. In principle the signal goes on forever, it's just a matter of how much money and technology they're prepared to put into a detector. The military has some wonderful technology, and applied to this problem they could undoubtedly do _far_ better than 30 meters.
One thing that might convince some doubters would be to set up another telescope nearby with plain optics and an eyepiece, then use a visible-light laser to bounce pulses off the laser ranging retroflector that Apollo 11 left behind on the surface - I have a picture of it here in a book called Eagle On The Moon (The incredible space journey of Apollo 11). Comparing it to a footprint it seems to be about 15" square, and maybe 15 yards from the lander.
You'd want to invite a half dozen well-known skeptics and let them peer through the eyepiece while they press a button to fire a laser pulse at the retroflector and wait the 2 and a bit seconds for the reflection to come back and appear in both the plain optical scope and the big electronically controlled scope with the digitally processed images. Then you'd want to be able to convince them that the two scopes are pointing at the same place, probably by taking a few photos of prominent features and matching images from the two scopes, and proving that that the features are in fact in the appropriate region of the Sea of Tranquility, as advertised.
Since there may be no other optical telescope nearby, they might want to use a tilting liquid mirror telescope, which should be cheap enough and portable enough to relocate next to the big new scope. These are under development:
http://www.casca.ca/ecass/issues/winter2000/feat ur es/borra/hgmirror.html
I know this will only prove the existence of a retroflective feature on the lunar surface near another feature that might or might not be the bottom half of a lunar lander, but maybe it's worth a try. If all of the lunar landers left similar retroflectors, it should be possible to account for all the Apollo missions this way, assuming they all landed on this side of the moon.
Slashdot Mirror
Any maximum quoted range for these things is
probably based on a reading device intended for
commercial use. In principle the signal goes on
forever, it's just a matter of how much money and
technology they're prepared to put into a detector.
The military has some wonderful technology, and
applied to this problem they could undoubtedly do
_far_ better than 30 meters.
Regards, RGC.
You don't have enough imagination.
Regards, RGC
Quite possibly they're using MicroStation,
fromk Intergraph. They have/had an OS/2 version,
and even their DOS versions would probably run under
OS/2.
Regards.
The dish is fixed into the bowl-shaped depression,
but the detection apparatus in the focal plane (if
that's what they call it) can move around.
Regards, RGC.
Sure there's an environment, but there's no ecology to worry about destroying. It's simply a matter of entropy.
One thing that might convince some doubters would be to set up another telescope nearby with plain optics and an eyepiece, then use a visible-light laser to bounce pulses off the laser ranging retroflector that Apollo 11 left behind on the surface - I have a picture of it here in a book called Eagle On The Moon (The incredible space journey of Apollo 11). Comparing it to a footprint it seems to be about 15" square, and maybe 15 yards from the lander.
t ur es/borra/hgmirror.html
You'd want to invite a half dozen well-known skeptics and let them peer through the eyepiece while they press a button to fire a laser pulse at the retroflector and wait the 2 and a bit seconds for the reflection to come back and appear in both the plain optical scope and the big electronically controlled scope with the digitally processed images. Then you'd want to be able to convince them that the two scopes are pointing at the same place, probably by taking a few photos of prominent features and matching images from the two scopes, and proving that that the features are in fact in the appropriate region of the Sea of Tranquility, as advertised.
Since there may be no other optical telescope nearby, they might want to use a tilting liquid mirror telescope, which should be cheap enough and portable enough to relocate next to the big new scope. These are under development:
http://www.casca.ca/ecass/issues/winter2000/fea
I know this will only prove the existence of a retroflective feature on the lunar surface near another feature that might or might not be the bottom half of a lunar lander, but maybe it's worth a try. If all of the lunar landers left similar retroflectors, it should be possible to account for all the Apollo missions this way, assuming they all landed on this side of the moon.
Regards, RDD