With the understanding that I'm NOT any SAR imaging technology expert but, I do have some radar imaging expertise and, I somewhat understand the rather impressive principals involved. Such as, if we were to reassociate the imaging performance of what the shuttle-bay SAR imaging of Earth was capable of achieving, in respect to it's impressive 60 meter SAR receiving mast and associated tight aperture that I believe was containing a 1024 x 1024 SAR/pixel sensor, that which ultimately produced those 1.5 meter/pixel raw surface resolutions from an altitude of roughly 225 km. I've just included another more conservative go at this lunar SAR aperture that should read somewhat better.
As for converting all of that into my bad form of truly dyslexic english:
From a distance of 225 km = 1.5 m per raw pixel resolution (not all that bad)
That's offering roughly a performance equation of 1 meter per 150 km
In other words (keeping it simple);
300 km = 2 meters/pixel
600 km = 4 meters/pixel
1200 km = 8 meters/pixel and so on (you do the math)
What if the shuttle (same applied equipment as being situated from Earth) were to be focused as looking towards the moon instead of Earth, that's obviously at an average distance of 384,000 km. Of course, if the shuttle-bay SAR were orbiting the moon at roughly 1/10th the Earth orbit distance, this would yield 0.15 meter/pixel worth of raw digital imaging, but that's certainly never going to happen for many reasons.
384,000 / 150 = 2560 meters or 2.56 km, of which this sort of imaging is rather pathetic performance as compared to almost anything optical, such as KECK-II with it's adaptive mirrors and of it's extremely fine CCD pixels should by now be capable of achieving as little as 4 meters raw resolution of the lunar surface (that may be a wee bit fuzzy and still without applying multiple image tacking nor of what PhotoShop resampling and of the unsharp mask can contribute, where either or certainly both of which could offer another 10 fold improvement of obtaining 0.4 meter resolution).
But folks and all of you equally snookered village idiots and/or simply fools; you'll need to be reminded that the shuttle SAR receiving aperture was limited to a mere 60 meters distance away from it's radar transmitting antenna array, as well as for the receiving aperture limited by those 1024 X 1024 imaging pixels.
The really good news is; if we were to extend that receiving mast out to the distance of 384,000 km (the lunar distance from Earth), obviously 384,000 km beats 60 meters by a good factor of 6.4^6 (6.4 million to one).
Taking advantage of such a terrific magnification performance is somewhat obvious, as even this village idiot figured it out. The further away you get the aperture the better.
If the best that our Earth orbiting shuttle outfitted mission or Earth based solution could image upon the moon was 2.56 km per pixel; that's going to become a rather substantial resolution boost of 2560 / 6.4^6 = 400^-6
Excuse please; that's a potential resolution of .0004 meters, as in raw imaging performance per pixel (actually that's going to be way limited by the radar frequency).
Now, lets improve upon that 1024 aperture sensor, pushing it towards what's currently available as being 4096 X 4096, that's another 4 times per XY format that giving us another 16 fold increase in overall image pixels. Just going in either the X or Y direction will obviously replace the .0004 meter resolution with a .0001 meter format.
In other words, we've improved upon the magnification of the shuttle imaging by another factor of 4X; which computes as 6.4^6 X 4 = 25.6^6
So far so good, but exactly how good is good enough; as we're now looking at a lunar surface resolution potential of .0001 meter resolution by way of using the same radar transmitting array, of which it isn't 1% of what any VLA of other Earth based arrays could provide and, certainly not 0.1% of what energy could be delivered from an Earth based transmitter. In reality, at such close range, the actual resolution will become limited to the radar frequency, where at best we're going to limit out at 1 mm if we could utilize 150 Ghz, or perhaps 15 Ghz for obtaining 10 mm resolution @2 looks/pixel (a 100 mm resolution would essentialy capture every pixel 20 times over).
In other de-snookering words once again; an Earth based radar transmitting site or collective of VLA arrays could easily outperform anything shuttle by delivering a radar spot or beam that's at least 100 times better in terms of focus as well as 1000 if not 10,000 times greater in energy output. Overall, that's 100 X 1000 or 10^5 better off than what the shuttle provided in radar pulsed energy concentration, where more than likely we'll be capable of exceeding a million fold improvement.
I believe the Earth based 100 times better transmitting focus by itself represents yet another obvious magnification improvement, taking the 25.6^6 magnification to the next level of 25.6^8 improvement over what the shuttle-bay SAR imaging offered.
Continuing onward in those other words; instead of the .0001 meter lunar resolution, we're now capable of .000001 or 1^-6 (that's one millionth of a meter at the target range of 384,000 km), where obviously the half wavelength of the radar frequency will severely limit this resolution to something considerably less but allowing many additional looks/pixel. If we were to go about imaging this technology upon something other than our moon, say Mars or how about Venus; as now we're seriously cooking with gas (without an optical lens nor mirror in sight).
When Venus is roughly 110 times further away than our moon, then obviously that's becoming a potential imaging performance of .000001 x 110 = .0011 meter.
Now folks and fellow snookered fools; I don't want to be alarming or implying anything unnecessarily suggestive but, it seems that SAR imaging by way of having just the minor receiving aperture portion as situated on the moon is offering a tad bit better than anything optical, by a factor of at least 400,000 over the best we've got and, well over a million times better than all the rest combined (that's including Hubble, which by the way can't see squat that's in the dark, nor of anything remotely close to the sun, by way of having that pathetic 20 degree minimum offset as fail safe). At least TRACE on the other hand has almost what it takes, just nowhere the magnification factor.
My fellow village idiots; What's best of all about SAR imaging:
1) there's absolutely no lens nor mirror distortions
2) there's obviously no lens or hardly any other refractions whatsoever
3) there's no multi hundred million dollar structural infrastructure
4) there's no source illumination requirements nor interference factors
5) there's a 16 bit depth of penetrating contrast as to detect content
6) there's obviously none of those multiple illumination shadows nor hot spots
7) the robotic lunar receiving base or module should be extremely energy efficient
8) the satellite performance aspects of the moon is rather stable and quite reliable
9) current lunar real estate is sort of clumping-moon-dirt cheap (the landlord is out of town)
10) with existing technology, we could affordably deliver this instrument to the lunar surface, without even having to expose astronauts to the extreme radiation as well as thermal stresses that should have killed any normal human within a few weeks to perhaps months of returning (that's shortly after losing all of their bone white hair), where possibly their lives salvaged today by organ transplants, including some of their own banked bone merel.
11) I almost forgot to mention; we essentially already have all of this SAR imaging technology and, that we've owned just about everything we've needed for well over a decade (just like we've supposedly owned those near flawless lunar landers for nearly 4 decades).
12) don't ever forget of exactly what 16 bits worth of such penetrating radar imaging can obtain that's way more important as well as imaging "proof positive" over anything CCD (irregardless of resolution). Then quite obviously, if you can manage a Magellan class flyover, taking fullest advantage of obtaining a 43° view perspective, that's certainly all the better, damn near as 3D worthy as imaging ever gets without your actually implementing dual imaging upon a given spot, which by the way isn't all that difficult to master if you already have a series of digital images acquired from an individual SAR imaging probe.
BTW; as you, Walter Cronkite and myself should know, NASA claims to have been to the moon (I don't know about yourself but, Walter and myself were situated right there), along with our radiation proof astronauts and even of packing along thousands of those KODAK film negatives, many of which utilized within those Hasselblad cameras, all of which somehow managed to never fog a single negative nor thermally impacted that flimsy (melted soft when hot @+250°F and brittle as ice when cold @-250°F) plastic film. If they can do all of that, with such trustworthy (late 60's fly by wire) lunar landers that were so reliable and well behaved that essentially all of the engineering drawings and outfitting (as flown) were tossed out along with the garbage, as if it's that simple and safe for a manned delivery of a SAR receiver module that shouldn't take but a few EVA minutes at best to unpack and deploy the SAR receiving aperture and of it's solar panel power supply and of the communications data link module, then getting oneself back into their aluminum foil radiation shielded lander and evacuate that otherwise nasty lunar environment, headed for the added safety of coming home onboard the massively shielded (5 g/cm2) command module, this certainly ott to do the trick, instead of a 14+ day mission, today we ott to be capable of pulling it off in 10 or fewer days worth of TBI exposure, which should compute into something quite survivable of perhaps 50 rem (.5 Sv) worth of impact, as long as there's none of those nasty solar flares during the EVA.
Even though improvements in robotic deliveries are fairly certain and, there's no longer an actual requirement for a manned delivery of such equipment (one-way robotic deliveries to the lunar surface should be a bloody snap as compared to accomplishing anything Mars or Venus), if cost and risk are not factors, thus the immorality of wasting such human as well as technology and energy resources, plus not to forget about leaving Earth with another multi-hundred tonne load worth of CO2 is not an issue, then by all means, we should do all of this the most expensive and most death defying way possible.
Lets see now (obviously that's intentionally excluding braille folks, sorry about that); if we have a Venus imaging resolution potential of .001 meter per pixel (since the half wavelength of the radar frequency well need to be 1 mm or less, as such the resolution will not likely become that good unless we're using such extremely high frequencies as 150+Ghz) however, the good news is that the ongoing imaging mission cost is all but 1% of what the overall spendy shuttle launched Magellan mission required, which delivered at best 10 meters and at worst 750+ meters due to the highly elliptical orbit, where an average of roughly 75 meter as was utilized for the mapping portions of Venus; so lets see what 75 meters / .001 = 75,000 times better resolution potential (or perhaps merely 7500 times better if we utilized 15 Ghz-Band radar frequency or even 750 times better off if we applied 1.5 Ghz radar) and, that's going to be delivering damn near a flat (undistorted or call it linear) imaging format, as there's nothing elliptical going on. Of course, Venus isn't always so close by (only every 18 months) but, seems that such performance yields sufficient room for imaging at ten times the distance of 42 million km, of which I don't think we ever get that far apart but, even if so, we're still looking at a potential of .01 meter resolution at a whopping range of 420^6 km.
As usual, my math could still be a little skewed, or perchance I'm running some sort of privet ulterior motive of my sneaking in certain truth agendas that NASA wanted to remain in the darkest part of their toilet of skewed science and physics (skewed history as well), so that only their story about all those Apollo missions continues to check out and, obviously the last thing we need is any radar imaging application that's offering a lunar surface detail of 1^-6 meter per pixel resolution, as damn it all, we could obviously read those serial numbers right off the lunar mission remains and, apparently we can't have that sort of thing going on, as such "proof positive" of SAR photographic technology and resulting truths would certainly become way too much to handle at one time.
In case you're wondering which planet I actually arrived from; I came into this way of reverse engineering SAR imaging, mostly because of all the unexpected flak associated with anything Venus, especially GUTH Venus. As apparently, God forbid, should there be another external to the club point of review of what's been imaged by the (dead horse) Magellen mission, irregardless of the consequences or of the opportunities, I'll guess (just like quantum packet communications) that we simply can't have that sort of truth just floating about the universe without first obtaining another NASA moderated stamp of approval. I'm not entirely certain but, after two and a half years and counting worth of receiving their warm and fuzzy flak, I believe I've discovered that there's another black hole forming, with my name on it.
Another delivery of the SAR imaging with only a slight steroid boost;
It's been months since I've evaluated the German space team results of the shuttle-bay SAR imaging of Earth, where they obtained 1.5 meter resolution that was achieved from having those image receiving pixels on the 60 meter boom or tower, while cruising along at 225 km. So, lets see if I can get this part right, or at least right enough
Instead of the 60 meter mast/boom, if using the moon at 384,500 km
Replacing the mast/boom by said moon, that's an image multiplyer of 6.4^6
If Earth VLA transmitters were utilized in place of shuttle array = X 10
If those SAR imaging pixels were upgraded from 1024 to 4096, that's = X 4
I believe that so far we're at 2.56^8 worth of further magnification
Venus resolution at 41^6 km = (41^6 km / 150 km) / 2.56^8 = 1.066 mm
Mars resolution at 56^6 km = (56^6 km / 150 km) / 2.56^8 = 1.458 mm
Obviously the radar frequency itself becomes the limitation at such close distances, so that the actual minimum resolution is going to become limited to 1/2 wavelength, or perhaps as little as 10 mm depending upon the radar frequency and of the number of looks per pixel. Thus, we obviously need to have a distance of 400+^6 km before the resolution starts exceeding the 1/2 wavelength aspects of any SAR imaging capability.
I believe I'm being conservative about those Earth VLA radar transmitters obtaining a 10 fold advantage, as I'm thinking we should be capable of not only greatly enhancing the energy per look but also of the focus, perhaps a factor of 100 fold is more likely and possibly a 1000X can be created if a sufficient number of globally spaced VLA transmitters were networked and implemented. This greater VLA source of radar transmitters and of signal reflectors might be asking a bit much but, at least it's Earth based (literally eliminating astronaut burn-out), easily configured and, there's almost no limit as to the pulse/peak energy that can be delivered and/or subsequently reflected back at the lunar based aperture.
Utilizing the Lunar Space Elevator CM and CCM as another SAR variation that's certainly worth doing, though obviously not nearly as magnifying but, there's absolutely no measurable to/from atmospherics diluting the signal, so the end results could be as good if not better.
If you feel I'm in error or just running seriously amuck, as in way low on medications, then please do inform this village idiot, so that I can continue polishing those door knobs. You never know, if I polish hard enough, accidently one of those doors might open itself, or perhaps the door knob is going to fall off and, if luck otherwise has it way, God only knows what I'll find on the other side; perhaps it'll be just another one of those skewed space toilets.