In the past we've had some good Viking images here. Soon - all too soon - we will not have Phoenix any more, but despair not! Now we can re-live Viking by playing with old images. They can be searched by sol at the PDS.

As an example, I've made a composite of the very last Surface Sampler activities at either Viking site. This is work done on Viking 2 sol 957 and imaged on sol 957 and 959. (someone can animate it if they like!)

We see two separate trenching activities at the same place, and a soil dump (bottom) and a conical soil pile made by the second dump (middle). (more obvious in an animation, I just can't make one on this machine).

Phil

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Attempt at an animation - not terribly good I'm afraid, I'm a clumsy beginner at this image processing lark.

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Great idea Phil... that will bring back some childhood memories.
1976 was a great year for a 10-year old

This is a set of four images documenting that last sampler activity. It is labelled with sol dates. The first trench was dug more than a year before the final digging event.
(EDIT: I have replaced the previous image with a corrected one, and fixed the text describing it)

This last digging event came so late in the mission that it is not documented in the trench maps published by Hank Moore et al. If anyone knows a final trench map that includes it I'd be pleased to know about it. Otherwise I will be making one myself in due course. Note - images 2 and 3 show no surface difference, just different lighting.

I will assemble other surface activity sequences like this, and I'd like to encourage others to join me.

Phil

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Ricardo Nunes and I worked together on some images. I made the grayscale images and he did he color.

You can see them on his site under the "super resolution RGB" tab. You can also see his work under other tabs.
http://www.astrosurf.com/nunes/explor/explor_vik.htm

Here's a bit more Virtual Viking - reliving the Viking missions to make up for the impending loss of Phoenix.

This is a comparison of the Viking 1 sample field - right side - seen before the arm operations began and after they ended. There are lots of changes - trenches dug, rocks moved, soil piles constructed (one at far left is on top of a rock).

Phil

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... and here's the left side of the Viking 1 workspace, before and after.

Phil

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Thanks Phil these are quite nice....

I have just edited post 4 above - and replaced its image with a corrected version.

Here is the Viking 2 before and after trench image - right side of the workspace. Lots of frost spots in the lower image.

Phil

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... and the left side...

Phil

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Here's another digging sequence from Viking 2. First, a view before anything happens. Then two views on sol 471, before and after a rock called Snow White was moved. The before image (left) also shows a disturbance just below the sampler arm, suggesting an arm touchdown on the surface some time between sols 454 and 471 (possibly on sol 471 just before the image was taken - but I can't find any documentation of it). The last image shows that the dark scrape made on sol 471 as the arm was retracted has been enlarged. This was the XRFS sample no. 12, but it failed to collect a proper sample.

Phil

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EDIT - the touchdown in the second image was made just before the image was taken. The arm touched the surface, was raised up, then extended to push the rock. As it was retracted it scuffed the surface to leave a scrape mark seen in the third image. The XRFS trench was dug later, but the arm struck a buried rock and did not penetrate enough to collect a sample.

Phil

Nice work, reading " A Passion for Mars " by Andrew Chaikin made me dug up some old treasures

Here's a pic from Viking:

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It's the full set of trench operations for Viking 2 in the primary mission.

Phil

Wow...I don't think I have ever seen those together.

The goldmine(s) for Viking Lander images:
Lander Picture Catalogs of Experiment Data Record - NASA Reference Publication 1068

Why? The images are all on the PDS.

Does one need a password to access the Planetary Data System ( PDS ) ?
http://pds.jpl.nasa.gov/

No.

http://pds-geosciences.wustl.edu/geo/vl1_v...vl_0002/browse/


http://pds-geosciences.wustl.edu/geo/vl1_v...vl_0001/browse/

I prefer this source, from which images can be selected by sol, or by clicking on mosaics for each camera to select pictures of a given area.

http://pds-imaging.jpl.nasa.gov/vikingl/vl_images.html

Phil

The Viking 1 site mapped in a new way... This is the polar projection of the landing site, which I posted some time ago, reprojected to HiRISE geometry. In this comparison, HiRISE is at the top and the reprojected Viking pan is below it. Mapping from ground-level images is very difficult, and grotesque distortions are inevitable, but this is the best I can do after several weeks and far too many iterations. The original is detailed enough to make a full photomap of the sampling area, and in that area the mosaic is controlled to fit the original mission map.

Phil

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I'm still perfecting that reprojected Viking 1 site map. Meanwhile here's a composite of images showing surface changes at the Viking 1 site. There were a few changes in soil patches on the lander itself as well, otherwise these were the only changes seen by Viking 1. For the first one, of course, the change I'm drawing attention to is the erosion by wind of Conical Pile 4 late in the mission. Several other artificial piles of soil were made and monitored but didn't change.

Phil

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Another of the things we can do so much better now than in the old days...

The Vikings carried mirrors on the sampler arm, and one of them could be viewed by one of the cameras to see underneath the lander. Seven images of the mirror were taken by Viking 1 on sols 528, 550, 582 and 594. They can be combined to produce a mosaic of the area underneath Engine 2 (the one right under the cameras) to look at the erosion effects of the engine during landing. The version made during Viking times was really bad! But now we can do it much better. This image contains two separate mosaics - they are supposed to fit together, but right now I don't have the old mosaic with me to compare and figure it out. They have been reversed to take the reflection into account and enlarged 2x. The bottom mosaic shows an erosion pit where loose soil has been blown away to reveal harder crusty stuff underneath. (EDIT: I found the location and fixed the mosaic)

Phil

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Here's the Viking 2 mosaic underneath Engine 2. The images were taken on sols 57 and 555.

Phil

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Those are truly special, Phil!

They are indeed! I'm gonna start saving my pennies for your forthcoming atlas...

I have edited my post above with the Viking 1 mirror mosaic - took out the old attachment and replaced it with one showing the two halves joined correctly. I found one 'accidental' mirror image from Viking 2 as well, that adds to coverage there, but I don't know exactly where the new frame fits. It doesn't actually overlap the mosaic. For reference these mirror mosaics cover an area roughly 20 by 60 cm across.

Phil

Another bit of Viking history now we are all thinking about the amazing views out past Endeavour crater in the Opportunity thread. After the Viking landing sites had been chosen in 1973 people began to have concerns about their safety. They looked for some extra-safe sites (as determined from earth-based radar) near the equator, the so-called C sites (A sites were at 20 north for the first mission, B sites at 44 north for the second mission. C would be used if A crashed or if all sites at those latitudes looked too rough in Viking images). C1 was just north of Capri Chasma, C3 at Schiaparelli crater, but C2 was at Meridiani. Here's a map showing three possible ellipses described in the minutes of the Landing Site Staff during Viking site certification in 1976. The top one just touched Endeavour crater.

Phil

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Fascinating (not a word I use lightly), Phil; did not know that.

One can only imagine how the Mars exploration strategy might have evolved had V1 landed in Meridiani on top of a nice piece of sedimentary pavement...

There's a lot of good stuff in those committee minutes. My next step is to go through the Viking landing Site Working Group minutes from c. 1970-1974.

Phil

Thanks Phil !
And to complement your good info, here is what was written a while ago + how Meridiani would have looked to the Viking Lander camera.
http://www.unmannedspaceflight.com/index.p...st&p=105769
Enjoy !

A good panorama for Viking 2 is hard to find. I have gone through the online CR-ROMs at PDS and extracted everything useful, and combined it here in one panoramic image.

For each camera I took morning and afternoon pans, and for camera 1 also a noon pan. Then, for each camera, I made a composite of the multiple views, with flaws or gaps in one fixed from one of the others. The tricky part after that was to combine Camera 1 and Camera 2. My intention is to mimimize obstructions by spacecraft components and maximize the visible surface, plus to combine the two views of the foreground into a full view of the sampling area. This cannot be done without introducing distortion in this view. Later I will rubbersheet the image to fit proper ground control for a photomap of the sampling field.

Phil

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Everytime I look at the Viking sites I still marvel at how lucky we were. Beautiful work as always, Phil.

Quick question: How did you account for V2's site slope in this view? IIRC the lander had something like an 8-deg tilt, so would have expected a very shallow parabola across the top of the FOV. Was this sort of "washed out" by the distant topography in your rendering?

Just curious, and forgive me if it's a silly question; my abject lack of image processing skills matches my lack of understanding of them!

The tilt was already corrected for in the assembled panoramas I worked from. They were made at JPL and saved in a rather chaotic collection of archived files in the PDS. The hard part was finding suitable files to use.

Right now I'm trying to project the pan onto a HiRISE image to make a photomap.

Phil

Gorgeous pic Phil, great work as usual. I could - and probably will! - stare at that for yonks!

Here's the Viking 2 pan wrapped into a circle with exaggerated horizon relief - greatly exaggerated, or you don't see anything. I did this for Viking 1 a while ago.

Phil

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Awesome job on both.

Amazing!

Thanks! I am doing some improvements to the panorama to get more uniform lighting - I just used the contemporary mosaics, now I'm making my own camera 2 pan with better morning lighting. Meanwhile, also working on step by step arm activity illustrations similar to some posted earlier. I must have Viking 2 finished by the end of July to stay on track.

Phil

Unique scenary. Surface is very rocky. That leads me to think on how lucky was Viking with landing!

As a tribute to Phil's gorgeous work, here is a VL2 controlled mosaic made in 2001 for a Mars educational exhibit built for the French section of the Mars Society... Enjoy !
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...and now for VL1 (especially made to show to the public the technical aspects of the robotic arm/soil sampler). Enjoy also !
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Those were AWESOME, VM, thanks!!!

Never, ever saw that V1 pan before; the arm was a beast indeed!

Spectaculars pictures. The VL2 landing is terrific. How lucky was VL2. Thanks Vikingmars.

Merci Olivier... the quality of the panos is absolutely stuning

Speaking of Viking... next week I'm at Brown University, going through the papers of Tim Mutch in their archives. I'm looking for the minutes of the Viking Landing Site Working Group and related materials. Should be fun.

Phil

Ooo...gotta be some good stuff in there, Phil, happy hunting!

Admit that I'm most curious to know just how close they came to selecting Meridiani as the V1 landing site.

OK, back from Providence with lots of goodies.

Nprev - they didn't get close to choosing site C2 - Meridiani. They had three sites at that latitude, Capri, Meridiani and Schiaparelli (C1, C2, C3), but they never considered any but C1 seriously.

C1 was called Capri, but it was not in Capri Chasma, part of Valles Marineris. It was on the plateau north of the canyon. A similar site was considered for Mars '84, an ambitious rover mission.

Phil

Phil I assume you worked with hi-res images? For comparison at this MSSS link are some VL2 mosaics (bottom of page). These are later versions of the ones I worked on during my internship at JPL in 1977.

http://www.msss.com/mars/pictures/viking_l...ing_lander.html

I have just photographic prints/negatives of the earlier versions, unfortunately they aren't in digital form.

Nice to hear you got a chance to look at Tim Mutch's papers. He was certainly a great person to have had the privilege of working with.

Welcome back, and thanks for checking that out, Phil!

So, when's the book coming out? Gotta admit that the hindsight gained from everything since Viking makes the project's history even more fascinating. 'There were giants in those days!'

My current plan is to submit the manuscript at the end of 2011, for publication a year later. That would be for Volume 1, up to Mars Express. Volume 2 would follow about 3 years later. But a final decision on a 1 or 2 volume format has not been made yet, and if it's a single large volume it will take 5-6 years.

Phil