I urge any DEM / GIS people to grab this...

ftp://ftpflag.wr.usgs.gov/dist/pigpen/mar...landingsite.zip
It's 150 meg

BUT - it contains detail related to TWO MOC NA DEM's - that between them totally cover Victoria and Erebus, and just to tempt and tease, there is a .mov and a .wmv in the root of the zip that show them rendered up with some vertical exag I think.....I can't make head nor tail of the data, but if someone could then I'd get all animated about it

Doug

I told you so...

http://www.unmannedspaceflight.com/index.p...indpost&p=53869

[quote name='alan' date='May 20 2006, 08:11 PM' post='55108']
Good idea Climber. The top of Husband Hill would make a good substitute for the rim of Victoria, although I believe it's higher than Victoria's rim.
View of Inner Basin from Husband Hill, green line shows where rim of Victoria Crater would be.
Edit: here is a single frame, full size to give an idea of how much detail could be visible on the far rim

Thanks so much Alan, that's exactly what I was trying to do. You're even saving me to learn how to draw circles Thanks to all others that told me how to do. I'll try soon.

"...... and I have impression that we start to see also other small, bright points all around!..."

They're BREEDING!

[quote name='centsworth_II' date='May 20 2006, 07:44 PM' post='55106']
climber said:..I'm not able to draw a circle...
I heard that Albert Einstein could not tie his shoes.

Thanks centsworth, could have been a compliment, but I'm still trying to make "circles" before going further in the tieing

That's a very interesting way of putting it... as you say, it must be one or the other, but it seems so unlikely sitting up there apparently alone. Ah Mars, you trickster you!



Now there's a thought for any rover builders out there currently chewing the end of their pencils at a drawing board: a very long, very thin arm - say, 2m? - hinged at several points, with a mirror on the end, capable of being winched over from one side of the rover to the other. With some fancy JPL precision-pointing fu, you could take images of the same spot from two widely separated locations without moving -- which would solve our current puzzle nicely! I'm not sure what it could be called though... the 'Visual Long Baseline Stereocam'? 'False Apperture Anaglyphagraph'? 'UMSF Disputeatron'? Far-Side-Quish-o-Matic?

Would you believe it! I made it!
Actualy, don't remember which method I used (Phyl's ?) but it worked (not sure I can do it again)
So, I'm pleased to show a better CIRCLE seen from above. Note that centsworth did a much better job by showing what we'll see from the ground, and that was the idea.
Anyway, enjoy a more professional circle :
Click to view attachment

Edit : as an exemple, what we can see now of Comanche from where Spirit is located, will be what we'll see of the base of the opposite rim of VC from were Oppy will take first pictures.

Impipak:

Cracking idea, Grommit - now, about that cheese...

Bob Shaw

Gosh some of the mnemonics would raise a chuckle.

'Visual Long Baseline Stereocam' - "vlabbs"
'False Apperture Anaglyphagraph' - "Fah-hhh"
'UMSF Disputeatron' - "Umms-fud"
'Far-Side-Quish-o-Matic - "Fuzz-quomm"

I quite like Vlabbs though

Nick

Updated Vote count as of May 22
Final Vote count due to Restricted Sols will be May 25

Here are the votes:

Far Rim

1. ElkGroveDan
2. prometheus
3. climber
4. MahFL
5. Joffan
6. bergadder
7. Stu
8. Nix
9. Bill Harris
10. centsworth II
11. alan
12. dilo
13. kenny

Near Rim

1. lyford
2. sranderson
3. helvick
4. Tesheiner
5. ustrax
6. Chris
7. RNeuhaus
8. dvandorn
9. imipak
10. Shaka
11. Phil Stooke
12. jamescanvin

And the 3 who can't make up their mind yet?
Please pressure these 3 to make a Vote by May 25 or we will have Ustrax chase after them for a hug?

1. djellison
2. Bob Shaw
3. mchan

The high reflectivity of the Beacon is a key issue for me. Most crater rims (any planet) have steeper faces overlooking the crater pit, and gentler slopes facing outwards away from the crater. We now know from extensive experience that the general rock in this region of Mars is bright, and the general overlying drift material is dark. If the Beacon was on the near rim, the orbital photos suggest we’d be seeing a gentler sloping side of the side of object, with more of dark overlay. If it’s on the far rim, we are more likely to see steeper exposed light-coloured rock. The Beacon’s brightness is clue to its composition, and the way it is facing.

I vote for the Far Rim.

Kenny

Why? Truth be told, the only currently 100% honest answer is that we don't know - we don't have the right sort of data, we're not close enough to make a clear cut call. I've not seen anything that makes it obvious, and until I do - I won't get off the fence.

Doug

[quote name='djellison' date='May 23 2006, 09:26 AM' post='55359']
Why? Truth be told, the only currently 100% honest answer is that we don't know - we don't have the right sort of data, we're not close enough to make a clear cut call. I've not seen anything that makes it obvious, and until I do - I won't get off the fence.
Doug

I never thought you took all arguments as been serious. I must admit that the one you submited 10 days ago or so is the best of all. You said "It's near rim because it's near rim". Stu's is quite good too : "sentimentaly it should be the Far rim" (not sure the quote is right). I'm afraid you'll be sat on the fence till Sol 935

I said near rim back when I didn't know it was just the beaconey thing at the time

Doug

Please pressure these 3 to make a Vote by May 25 or we will have Ustrax chase after them for a hug?

Awww, no-one should be pressured into voting, this is just meant to be a bit of fun isn't it? If people want to sit on the fence, that's fine. Me, I'm just going to wave at them sat on their fence from over here on the FAR RIM, dangling my feet over the edge of the FAR RIM, kicking my heels against the hard rock of the FAR RIM, dislodging little pebbles that then bounce and skip down from the FAR RIM and roll across the floor into the dust dunes...

Besides, something tells me there ain't a power in the 'Verse that would stop Ustrax giving someone a hug... (Firefly fans will get that! )

Please pressure these 3 to make a Vote by May 25 or we will have Ustrax chase after them for a hug?

I suspect threats from tentacles will work better on Bob Shaw than a Ustrax hug. But since I am next to Bob on the list of undecideds and I am not fond of tentacles that aren't cooked calamari, I'd best get off the fence.

3 pixels is about 1 meter according to an earlier post. I imagine it as something that looks like Comanche with one edge, fracture, or face catching the light. For the brighness relative to the ground nearby, it seems to me that it is smaller object that is closer rather than a larger object or formation that is ~60% farther away. And so I cast my vote for the near rim.

Ah ah! 13/13.
You know what ? Unless we decide to corrupt other people to come on board and as the "Boss" will not pronounce, it will be the "King of the World*" that will make the difference
* I told you yesterday, in his BBQ scene picture, Astro0 realy captured everyone's Spirit

"...Gosh some of the mnemonics would raise a chuckle...."

When I was a grad student at Washington University, the NASA Regional Planetary Imagery Facility had a database program for selecting planetary images based on image parameters and geographic coverage, called Better Image Retrieval Program (BIRP).

I <sadistically> proposed a companion or extension program: Graphic Utility Routine for Global Localization and Enhancement (GURGLE).

The reactions were distinctly pained.

Far rim.

Why? That's what the pros are saying, have they steered us wrong yet? (No Purgatory jokes, please).

Brian

Though I've been leaning towards 'far rim', I have to agree with Doug.
There is not enough evidence either way, so I am going to sit on the fence with the rest of the fence sitters

Ok I come out as a fence sitter too! Hardcore fence-sitting like ours: http://legofish.com/photoblog/archives/fence.jpg is even harder (more masculine) than common pole-sitting: http://en.wikipedia.org/wiki/Pole-sitting

I'm too woefully free of facts to be able to even find a fence, so I'll stick to my early decision that The Beacon is a far rim feature (although I attributed the Beacon to a small crater on the far rim, which I think has been debunked because the viewing angle is always wrong). Nevertheless, in theory the far rim will present a larger face of fresh evaporites than the near rim which (unless its been weathered) shows us the old surface material.

Looks like Oppy spent the weekend examing more crossbedding. Festoons, anyone?

Yikes! It wasn't me! You'll have to give the credit to someone else.

The actual cartography pro, Phil Stooke, and ranking amateur, Tesheiner both say near rim. I respect their opinions enough to be very uneasy about my far rim choice. But I think the uncertainties are enough that even the experts are going out on a limb to make a definite pick.

The beacon is a discontinuity, so it is instictive (for me) to see it as part of the far rim, discontinuous from the foreground. But it is small enough (less than 1m?) that it could be an odd uplifted outcrop or loose chunk on the near side -- not necessarily ON the rim. I'll stick with my far side guess for the romance of it -- the highest outcrop overlooking Victoria Crater... the Burns Cliff of Victoria Crater.

It would be nice to roll right up to the feature producing the beacon if it is near rim. But anticlimatic if it turns out to be just another nondescript chunk of evaporite. (How blasé we are getting about rocks on Mars.)

Yikes! It wasn't me! You'll have to give the credit to someone else.

Sorry Alan! You know, censtworth II just filled a full page of replies and I though it was him
Thanks again Alan.

My reason for choosing a near-rim location is this... We see a broad relatively smooth slope leading up to the beacon. As others have said as well, if the slope is the inside of the crater we should see a broad band of outcrop all along it, probably with lots of irregularities clearly visible. So most likely we are seeing the near side of the outer slopes of Victoria. Then the question is, is the beacon on that slope or just peeking up over the top of it? I feel that, if it was on the far rim, we would have seen it move either sideways relative to the dark patch, or up or down, as Opportunity has moved so much since it was first seen.

Phil

My problem with that is I don't see anything on the overhead view that would explain such a protruberance. The beacon appears quite higher than the surrounding terrain, would you not expect such a feature to cast a noticeable shadow? The section on the near rim where the line of sight crosses does not appear as reflective as the far rim promontory, either. And there are other sections on the near rim that appear quite similar and I would expect we would pick them up as visible "beacons" also.

I guess I have to stay in the "peekaboo camp" but on the bright side (no pun intended) for the Near Rimmers, when choosing from a position of near total ignorance (like trying to pick the fastest checkout line at the supermarket), I have an abysmal (pun intended) track record.

Brian

Tentacles, tenterhooks, tent-pegs... ...I confess that I am a fence-sitter to the end. I sway both ways (quiet, Phil!) and then... ...change my mind. Probably it's the Martians having a wee joke, put up to it by that naughty comrade Mars-3.

Bob Shaw

Add me to the far rim crowd.... Just think it must be an inside-of-crater feature.

> My problem with that is I don't see anything on the overhead view that would explain such a protruberance. The beacon appears quite higher than the surrounding terrain, would you not expect such a feature to cast a noticeable shadow?

I fear we are trying to take too much information from a 1-3pix feature on a compressed jpeg image. Since it was first seen on the pancams, the only images available are always on the same L2R2 filters ; shots on different filters might tell some additional information about it, but there are nothing available.

Besides, shadows on MOC images, either it's presence or absence, may play tricks. Remember for instance the *huge* dunes we (or at least me) were expecting on the way to VC, which were actually dark cobbles fields in-between the ripples.

My feelling is that the "real truth" will come from the parallax measurements once the rover gets closer to Corner Crater. Independently of how big (or small) the beacon is on the images, its angular position relative to C.C. should tell where is it located; near rim or far rim.

Possibly 'Graphical Routine for Global Localisation' (GRGL) would have been better received?

ObOnTopic: Ustrax was right, I think - there are other beacon-like features emerging from the pixel soup, along the horizon to the left and right of the original Beacon. Naturally I think this makes it even more obvious that we're seeing a single small tilted plate of rock that happens to expose a relatively white, undusted and unweathered plane towards the approaching Oppy. The other pale patches are similar 'plates' surrounding the nearside rim, just like those seen at Endurance.

I'm sure there's a technical name for those sort of rocks - there seems to be one for everything else - could one of the learned scholars of matters mineral enlighten me?

Bob said:

"I sway both ways (quiet, Phil!) "

I'm not rising to your bait, Bob. What do you think this is, "Up Pompeii"?

Phil

As for the Peculiar Protruding Prominance, I'm still a staunch "Far Sider", and presume that what we see is the near slope of that little 'straddler' crater poking up over the bluff before it.

The 'beacon' location as given in this flashy "Near Sider" propoganda release nicely matches in-line with the crater at the top of the far slope behind it as seen in this image of the Victoria Crater approach.

This crater really looks to be on the very rimtop and could slope up about a meter, maybe? no?

My teenage daughters Laura and Catriona tell me that I am a “geek” and that I should “get a life”. Much as I have resisted this harsh judgement so far, as we continue this Near/Far Rim discussion I am beginning to believe it….

Although I'm a far-rim rocker, on a scale of 1 to 10 this barely bumps a 2, and is practically tilting at a Beacon-esque windmill. The interesting stuff is at our feet, which is undergoing significant change.

--Bill

I like this argument. But there's no reason that a block of evaporite couldn't have been blown out of the crater onto the near rim. The bright face could just as easily be facing outwards, away from the crater. Just for the sake of argument, I'll vote near rim.

David

At this distance, around 1000 meters, PANCAM view is still blurr due to lack enough of pixels per square meter images. Then, Spirit is going around 17-18 meters/sol. At the distance of 500 meters, the image would be twice neater. So it would be around 25 Soles, around 2nd week of June would be the "D" Day of surprises and faintings.

Rodolfo

Now if we are seeing the FAR rim beacon, (I don't even think its a beacon, just a horizontal outcrop on the far rim) through, a gap (window) in the near rim, then the parallax measurements will not help in the horizontal plane, ( as all we will get is the measurement to the gap) It may reduce as we swing towards C.C. and that may give us a cue, or not, with the near rim covering more of the Far rim Beacon.

[quote name='RNeuhaus' date='May 24 2006, 04:27 AM' post='55497']
Then, Spirit is going around 17-18 meters/so.At the distance of 500 meters[/s], the image would be twice neater. So it would be around 25 Soles, around 2nd week of June would be the "D" Day of surprises and faintings.
Rodolfo

Well, she'll still be some 10.000 km from the beacon

Yet there is still some merit in this exercise. Scant evidence is a common predicament in planetary science, so the ability to make analysis and argument based on limited information is required, and here we can test our various analyses later. It's not just about who was correct, but which analytical appoaches were useul.

Updated Vote count as of May 23
Final Vote count due to Restricted Sols will be May 25

Here are the votes:

Far Rim

1. ElkGroveDan
2. prometheus
3. climber
4. MahFL
5. Joffan
6. bergadder
7. Stu
8. Nix
9. Bill Harris
10. centsworth II
11. alan
12. dilo
13. Kenny
14. Marz
15. Oersted
16. atomoid
17. BrianL

Near Rim

1. lyford
2. sranderson
3. helvick
4. Tesheiner
5. ustrax
6. Chris
7. RNeuhaus
8. dvandorn
9. imipak
10. Shaka
11. Phil Stooke
12. jamescanvin
13. mchan
14. DFinfrock

Fence Sitters and yes this is just a fun Game of figuring it out what side Beacon is on.

1. djellison
2. Bob Shaw
3. Zeke4ther
4. Tman

[quote name='kenny' date='May 24 2006, 09:09 AM' post='55512']
Yet there is still some merit in this exercise. Scant evidence is a common predicament in planetary science, so the ability to make analysis and argument based on limited information is required, and here we can test our various analyses later. It's not just about who was correct, but which analytical appoaches were useul.

kenny, I like what you say here. I'll add that we are lucky to have a lot of time in front of us and that where beacon is is not that important. This is not to compare to the pressure of a fly by in the Voyager's program for exemple when you HAVE to get as much value as possible out of it. They used to start shooting picture months in advance and do exactely what you're saying.

I think all this speculation about the location and nature of the Beacon is not only great fun, it's actually in the true spirit of Exploration. After all, exploration - whether it's here in the jungles or arctic wastes of Earth, or out there, on the plains of Mars or amongst the stars - is all about looking to the horizon, looking as far as you can, finding something interesting "over there" and trying to make sense of it, even before you reach it. So what if we don't have very good images yet, or accurate paralax data, or a clear line of sight. We did exactly the same thing as Cassini started its first approach to Titan, speculating about the true nature of the light and dark areas we saw. We did exactly the same as the first grainy Huygens descent images came in, wondering what we were seeing as the probe swung round and around. No-one said "hang on, we don't have a clear enough image yet, everyone calm down and wait"... we were all caught up in the excitement of seeing something new, something no-one had ever seen before, remember? This is just the same for me.

Okay, so Beacon might just turn out to be a chunk of ejecta, or an outcrop catching the Sun, or something even less interesting, but it's got us all talking, got us all working together to make sense out of it, and it's making VC an even more intriguing destination that it was when Oppy headed south.

No doubt fascinating and useful science will come out of the approach to, arrival at and study of VC, but don't underestimate the worth of exploring for wonder's sake guys; it's what took us to Mars in the first place.

I still believe it so...
And as I'm not a fence-sitter, for good and bad, I'll stick to my near-side rim idea...
From the image I've blown some time ago, this one:

http://www.unmannedspaceflight.com/index.p...869&#entry53869

and where appeared to be some other features surrounding the beacon, I draw a line over the horizon rotated it and applied it to the area on the near rim where is supposed to be the beacon and, forgive me those guys on the other side of the crater, it seems to me that there are some correspondences between some points...Don't know if measurements will throw down my idea or support but to me it looks like we are seing this:

http://i16.photobucket.com/albums/b14/ustrax3/beacon6b.jpg

Hello

According to Ustrax observation and deduction, I for those who think that is the far rim. Also, my opinion is that the far rim we see on the pictures.

Quoi?!

Are you telling me that my 'observation and deduction' made you jump to the far side of the crater?
...I'd better return to the abyss before we run out of players...

Oops! I made a mistakes. I'm confuse. The NEAR rim I wanted to say, the near rim... (I need to re-read the writings ... I'm french....)

Ohh...I see...
In that case...:

http://i16.photobucket.com/albums/b14/ustrax3/nru2.jpg

I know this is slightly off the topic of near rim or far rim (I'm voting for far rim), but I am curious to get a sense of how high above the surrounding terrain this crater all goes. Opportunity is about a kilometer away from it now, and it seems as though this wall can't be much more than a few meters high, though clearly hundreds of meters wide. This seems like a strange crater to me.