Rim of Anaxagorus A

About one third of the way down from the top of this frame is a truly gigantic boulder with a very smooth sun-facing side, triangular or diamond in shape, casting a very long shadow.

Nice pictures. The most intriguing thing is that the skin of elephant is very common on the Moon surface. In spite of the fact, these might be originated by any kind of erosion that happens in the Earth.

I seems that they might be occurring when the below surface might have fractures where the regolith sink and it is smoothed by the solar bombard of particles. The others suppositions are that the boulders caused by the impacts are rounded or disintegrated by the solar influence after thousands millions years. Hope this mystery would be cleared up soon.

As with CTX and MOC, even and odd pixels go through separate signal chains and the offset between them is still being adjusted in these early images.

BTW, the story of how we were able to make NAC run almost 4x faster than CTX with only minimal changes to the hardware is yet to be published

Useful link to ubicate where is LRO?

Quite impressive pinnacles and spikes around Anaxagoras A...

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How high is this feature, anyone?

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back of the envelope, right triangle problem...
~50 pixels long shadow at 2 meters per pixel resolution == 100Meters shadow...low sun angle (?) degrees
(shadow may be running on a downhill slope, making it longer...)

my guess is 4-8 meters tall (WAG)

Beware anomalist thinking. The sun angle is likely to be so low that these could well be quite ordinary boulders or clumps. Without knowing the sun angle and even the local topography, you just can't tell.

I noticed that on a couple of the images but not all. More interesting is that the Zoomify image on the LROC website doesn't show that artifact.

Zoomify does....but it only zooms to 100%. If you screen grab and zoom in more - the same effect is in there.

Anomalist? Moi?! How VERY dare you!!!

Why, I'm a monolith of scientific scepticism!

Point taken.

Still cool pics tho.

You won't notice it on summed images because for those the even and odd pixels are averaged in the instrument. And as Doug says, you have to zoom all the way in to see it on a full-res image, and even then it's less noticeable on some images than others.

I guess my point was that the LROC folks are doing a good job of modifying the raw data so that the striping effect is almost non-existent on the Zoomify images. I went and zoomed up to the pixel limit, grabbed the image and dug deeper. Yes, there is a hint of that striping in some of the image "blocks" but it looks more like a "jpeg-ing." They're very nice anyway!

Some images have it - some don't - as Mike explained. For those that have it - it IS in the Zoomify images, you just need to zoom in more than Zoomify can. There's no gradient between existing and non existing. It's one or the other.

Tiny bit of LROC WA mosaic from the calib image released.

It'd be interesting to see if we can pull out a bit of colour variation

There's a 'flyover' movie posted on YouTube today.

I am speechless...

I ran the photo's particulars through SPICE and get a sun elevation of 0.42 degrees, so it's just sitting practically on the horizon and rising.

30JUN2009 16:04:33 UTC, center lon -7.890545, center lat 72.20735 -> sun elevation 0.422, sun azimuth 89.395

This is a stupid query, but why are all the images North down and South up

The usual views of presenting images is to have North up and West on the left -- in accordance to the cardinal points as laid down for the Moon by the IAU in 1961. Will future images see a change in orintation?

John

Uncalibrated, raw imaging swaths taken on a descending node in a polar orbit will have north pointed down. Map-projected products take care of this.

http://lroc.sese.asu.edu/news/index.php?/a...s.html#extended

Cropped / enhanced crater from the floor of Compton Crater...

http://twitpic.com/9zav0

What instrument will be able to "see" the dark parts of Moon, as the bottom of the Compton crater?

The LAMP instrument takes advantage of background ultraviolet (Lyman Alpha hydrogen emission) coming from all directions from stars & also scattered from hydrogen clouds nearer the solar system to see in otherwise dark areas. Pretty fancy I'd say!

SpaceListener: Mini-RF. This instrument is also flying aboard Chandrayaan-1 and we already have maps:

http://www.nasa.gov/mission_pages/Mini-RF/...edia/index.html

BTW I'm amazed to see objects as small as rocks on the surface on the Moon! These NAC photographs are AWESOME.

I dunno -- some of those rocks are likely the size of a football stadium, if not larger.

-the other Doug

Knowing the fact the current resolution is about 1 meter per pixel at least and these rock are larger than a pixel (or even a few pixels), you are right. But they look cool

OK, on topic:

http://lroc.sese.asu.edu/news/?archives/74...gle-Camera.html

A new WAC image has been published

Didn't see this recent news item mentioned here:

http://www.spaceflightnow.com/news/n0907/06kaguya/

"Japan's now-finished lunar mission found no water ice"



The LRO press kit mentions two competing theories for why Clementine saw decreased neutron flux at the poles, both involving absorption of same by hydrogen: either in water form, or alternatively hydrogen deposited from solar wind could be more stable and accumulate more due to the cold polar temperatures.

I don't think anyone has ever anticipated finding glaciers of white ice just sitting in the bottoms of polar lunar craters. Exposed ice would sublimate quite quickly when exposed to the vacuum.

Instead, I believe the expectation is to find an "icy regolith" layer (something like a permafrost layer) underneath a completely dry layer of regolith. The minute gaps between the grains of the covering regolith cap would be enough for the tiny amount of sublimation that results in the hydrogen signature detected by Clementine and Lunar Prospector.

-the other Doug

When the Lunar Prospector announcement was made the figure of "1% water" or something like that was given, which added up to a lake's worth if the total input is a gazillion tons or whatever. Later it was pointed out that hard concrete has a similar amount of water, so extracting drinking water seemed less plausible. Let's hope the figure is quite a bit above that!

BTW, according to the materials for the LAMP instrument:



Would that imply that LAMP is only suited for detecting surface ice/frost?

http://lroc.sese.asu.edu/news/?archives/77...Moon-in-3D.html

LROC images in 3D

Yes, Dvandorn, I think the situation on the moon will be similar to what Phoenix found on Mars -- ice (or an ice rich regolith) covered by a relatively thin layer of dry regolith.

Very nice bit here on the whole LCROSS cruise phase setup -- flight director for LCROSS. Well worth a read.

John
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A couple of nice new LROC images posted on their site in the last couple of days. This is a really nice camera!

Phil

This is a tiny detail from the upper wall of Burg crater in the latest LROC image. Nice dust streamers - I don't recall anything like this in Apollo or Lunar Orbiter images.

Phil

Click to view attachment

Hmm. And you of all people would certainly know, Phil.

That's really interesting. If they are in fact dust streamers, what's the sorting mechanism to generate them? It's gotta be a thermal expansion/contraction thing, but nothing obvious springs to mind.

Yes...hmmm...I wonder would quakes be a contributing factor?

Phil, is it odd that the albedo of these streamers is lower than from where they originated from -- I would have thought the layer of dust that rolled down wouldn't have changed it much?

John

Particle size and surface texture affect reflectivity as well as albedo. We can't separate those factors yet and say the albedo is different.

Electrostatic effects might move dust while leaving coarser material, allowing it to slide downhill on its own.

Phil

How long ago might such a landslide/deposit have taken place? A billion years? Only when the crater formed? Or perhaps more recent?

I would guess that the large wall slumps defining the crater terraces occurred immediately after crater formation, the small local landslides which form rubbly deposits on the terraces take place sporadically every few million years, and that these dust treamers are formed by gradual, continual (or short timescale episodic, like every year or two) ongoing processes.

There are some nice rolling boulder tracks below this area.

Phil

Thanks Phil

OT: The half-covered crater just on the boundary in the Frigoris Image is simply excellent at very high res...WOW.

John
PS...I see the color camera is now working fine...yeah...sacrilegious, I know
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The Moon ( or Selene - I just do not feel 'the Moon' does her justice) sure ain't boring...

Every time we increase resolution on a planet/moon, a whole new world pops into view. LROC will help reveal processes that operate on a large, airless, volatile free body.

How exactly do electrostatic and exospheric efffects operate, long term and short?

I expect the unexpected.

WOW..

Craig

http://lroc.sese.asu.edu/news/?archives/84...d-Boulders.html

Bright crater rays and boulders

http://lroc.sese.asu.edu/news/?archives/85...nd-craters.html

Tsiolkovsky crater

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Although its not possible to see in the LRO image browser, this image has many boulder tracks in it if you download the tiff and adjust the contrast/brightness appropriately.

I have attached a sample.

Yes! This sample is just another example of rock movement.

Because this is what I think has happened while looking at these images.

We can clearly seen the trails. But what could have caused this? The Moon is a dead body for millions of years.

Seismic shaking caused by nearby impacts?

Phil

Have they mostly slid or tumbled ? Some tracks remind me of Spirits' RF

Eoin

Pretty weird seeing craters on the tops of those Tsiolkovsky ejecta blocks. Obviously you know they must be there, but it just seems odd seeing them in 'solid rock' compared to the surrounding regolith.

p

Back in the old Lunar Orbiter days they developed alot of theories for why the boulders eventually rolled downhill. I will have to did up the old reports. I recall thermal cycling and impacts of meteors causing tremors factored into it.

My main interest in these is that they permit the deduction of regolith mechanical properties without having to land there. We don't really have any instruments to deduce these mechanical properties remotely. Landers or rovers could of course, but that is way too costly. During the Lunar Orbiter days, they found a slew of these in the very high resolution images (~1-3m/pixel, which only covered a small percentage of the surface) and derived regolith properties in preparation for Apollo landings.

One of the concerns about the regolith is how much variation there is in its properties over the entire surface. Since interest exists for the near polar regions, it would be nice to be assured the properties are the same there as near the equator. Rolling boulders should be distributed fairly equally over the surface and if there aren't many near the poles, that is significant.

Also, looking at these images, I had supposed there would be many more rocks and boulders (which would be especially visible at some of the shallow Sun elevations for the images), but there seems to be many more craters than boulders (~an order of magnitude). Does this make sense?