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And one of the reasons why I don't take arguing politics too seriously aracer. Because I am fully aware that most people, like me, have already decided before the argument even starts.
There's no arguing with that!
PhD and 5 years postdoc research in electron microscopy so have some vague idea about optics since you brought it up
Splendid. Well done you. And yet, despite that fine education, you still seem to be suggesting that I'm wrong and that Hubble (or some other secret sattelite) should be able to see the rover. Try applying your PhD to these figures:
A telescope's angular resolution (ignoring the muddying effects of Earth's atmosphere) is limited by the diffraction of light in the optics. This diffraction limit depends linearly on the telescope's aperture so that at visible wavelengths the resolution is about 14.1/D arcseconds where D is the aperture of the telescope in centimeters. For the Hubble Space Telescope (HST) in low Earth orbit whose mirror is 2.4 metres (7.9 ft) across, the diffraction limited angular resolution is about 0.059 arcseconds which corresponds to about 110 metres (360 ft) at the distance of the Moon. In order to resolve an object 1 meter across into a single fuzzy spot would require a telescope 110 times larger than the HST, or about 250 metres (820 ft) across. But to resolve such an object with enough detail to recognize what the object is would require perhaps 100 times more resolution still, or [b]a telescope whose aperture is some 25 kilometres[/b] (16 mi) across. Additionally, any ground-based telescope would have to mitigate against the effects of seeing, beyond what is currently possible with adaptive optics.
I never said the mooted spy satellite was looking at the moon or that it CUOLD resolve the rover, I said, in the context of conspiracy theories, that such a thing existed and was looking "downwards" ie. towards the earth. I do happen to believe that is the case, and I think thats how/why they solved the spherical aberration problem so quickly.
Your post
"I'm pretty sure we'd notice a top secret satellite with a mirror that was 25 kilometres in diameter"
reads as you suggesting/believing that the mirror in the HST was 25km across. Your cut-and-paste suggests that is the required theoretical diameter which I assume is where you got the figure from, and you weren't in fact suggesting the HST was so vast. I've re-read the sentence and thats still how it reads to me. The joys of the tinterweb.
Yes, whereas you saying:
>Graham S said;
>Even Hubble doesn't come close to having a large enough telescope to resolve an image of the rover - never mind the frickin tyre marks[b]dont be so sure.[/b]
reads a lot like you're not so sure that Hubble isn't big enough to see the rover.
And incidentally, it took them twelve years to fully correct the error with the lens (Hubble was launched in 1990 and the COSTAR correction was required till 2002).
"dont be so sure" as in a conspirational "Aha, but...."
seems we're arguing about nothing, other than the difference between "what the writer implies and what the reader infers".
Still, when the new lunar orbiter gets there its high resolution camera will be able to resolve object sizes down to approx two meters, so will be able to pick up the landing sites. Of course, any pics coming back will have had the landing site photoshopped in by the poor bugger crammed into the orbiter with a MacBook Pro and Adobe CS 4.
You mean like these, taken by the Lunar Recon Orbiter last week?
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oooooh its interesting when its something you know nothing about
Thanks Graham, I had a look for those and was trying to link but my edit timed out.
Here's the original article:
[url] http://news.cnet.com/8301-19514_3-10289551-239.html [/url]
I'm sure RB's conspiracy would have these pics covered. Where is he when you need him most, eh?
I'm sure RB's conspiracy would have these pics covered. Where is he when you need him most, eh?
Under sedation I hope ............ how mad are those eyes ffs ?
[img] http://images.fotopic.net/?iid=yw4smg&outx=480&quality=70 [/img]
But if you miss that much, I believe he does signed copies - donations to his favourite charity.
I think he looked better before he shaved the beard:
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Naaa, just interested in how, exactly, he'd manage to explain those pics ^