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Unmanned Spaceflight.com _ Opportunity _ Heatshield
Posted by: akuo Dec 22 2004, 09:03 AM
Heatshield AHOY!
:-)
Posted by: OWW Dec 22 2004, 10:05 AM
What a mess!
Posted by: djellison Dec 22 2004, 10:21 AM
Wow - lots of chunks 
I think somebody flushed the toilet on Opportunity - we're getting a LOT of pancam imagery from Sol 114. Imagery that was taken in MAY!!!
I guess being out of the crater really opens up the UHF passes for a full horizon to horizon pass every time - 15 minutes of 256kbits (190Mbits+ ) - instead of just the top 120 degrees or so when you're in a crater
Doug
Posted by: Sunspot Dec 22 2004, 10:34 AM
From the long range images of it - it didnt seem to "look" too badly damaged, now were seeing it up close it looks much worse lol. And that must have been a looooooooong drive on sol 324. 
Posted by: djellison Dec 22 2004, 10:50 AM
There you go ladies 
I've labelled the big bits so we can sing from the same song sheet. I'd suspect that they'd like to look at A for the science of the imapct, and almost certainly E because it'll be a nice piece of heatsheild detached from the danger zone near C and D
I think C/D will be avoided like the plague - too much chance for danger - but when we get the R navcam frame for the middle of that mosaic - I think we'll see that B is 5 - 10m further away than C/D. If they're happy to look at B -then I think we'll see A - B - then possibly E - or just leave after B. But - like the Parachute and backshell - C/D has too much potential to hurt the rover - it's got to be 2m tall
For scale - from A to E is about 38 metres - and Eagle Crater was about the size of the gap between B and E
Doug
Posted by: Sunspot Dec 22 2004, 11:03 AM
Posted by: Sunspot Dec 22 2004, 11:08 AM
Could the object you labeled C in your picture actually be a rock?
Posted by: OWW Dec 22 2004, 11:17 AM
This is one mangled piece of metal. When I look at a picture of the original heatshield I can't say that I recognize any piece we see here... 
Can someone identify the part(s)? And Doug, I think Sunspot is right. Chunks C and E look like rocks.
Posted by: dot.dk Dec 22 2004, 11:37 AM
Now where did that BIG trench go 
How can it be bended and folded like that without digging a deeper hole in the ground?
Did it land on a rock on the ground perhaps?
Posted by: Sunspot Dec 22 2004, 11:42 AM
Here's the pancam image of the hole :
http://qt.exploratorium.edu/mars/opportunity/pancam/2004-12-22/1P156949363EFF4075P2357L7M1.JPG
It's probably deeper than it looks, we're not close enough to get a look at it
Posted by: dot.dk Dec 22 2004, 11:44 AM
So it jumped out of the impact hole and did not make a "genesis" impact
Well then the hole is free to study, great 
Posted by: djellison Dec 22 2004, 11:45 AM
When I was refering to C and D - I meant the two parts of that central lump which pancam has resolved into being one lump. I'm shifting the naming of D to be whatever piece of heatsheilf is behind C - and keeping it upright.
That piece way out at E really is a bit of heatsheilf. Colour images show that - 
Apart from, you know, LOADS of bits of heatshielf - we can see three springs that pushed the heatsheild away from the backshell as well. There's three more out there somewhere
BIG picture
In there is a tiny pic of one of those brackets that held the springs pre launch
Doug
Posted by: djellison Dec 22 2004, 12:00 PM
Posted by: djellison Dec 22 2004, 12:01 PM
It'd make a LOT of sense to approach that rock - it's a nice size for IDD work.
Park there - and IDD the rock whilst Pancaming the heatshield
Doug
Posted by: akuo Dec 22 2004, 12:17 PM
These rocks seem to attract Crap from Outer Space.
As you all remember, Oppy just about hit a similar rock just before bouncing into the Eagle
crater. And we haven't seen one like it for hundreds of metres.
Posted by: djellison Dec 22 2004, 12:29 PM
I think it might be two springs over by B - so that's four - and possilbly one just to the left of impact crater A
Doug
Posted by: mhoward Dec 22 2004, 01:46 PM
crater. And we haven't seen one like it for hundreds of metres.
Maybe the rocks are magenetic?
It is odd.This is a far out idea, but what if the rock was actually ejected from the impact site. There don't seem to be any marks in the sand that would indicate that, but maybe they've been covered up in the months it took Oppy to get out here. Just a thought.
Posted by: jamescanvin Dec 22 2004, 02:49 PM
Why am I reminded of Beagle 2 when I look at these pictures?!!
James
Posted by: djellison Dec 22 2004, 03:04 PM
crater. And we haven't seen one like it for hundreds of metres.
Maybe the rocks are magenetic?
It is odd.This is a far out idea, but what if the rock was actually ejected from the impact site. There don't seem to be any marks in the sand that would indicate that, but maybe they've been covered up in the months it took Oppy to get out here. Just a thought.
No - I think that rock lived there -it's got a slight upwind highlight to the soil around it which is a slow forming feature I'd imagine.
there are other bits and peices ejected out from around there- but I dont think that's one.
And HELL yeah - I want to see what B2 looks like
Doug
Posted by: azstrummer Dec 22 2004, 04:31 PM
Great picture Doug. My guess, based on how bent up this heatshield is, is that the thing came down sideways so there might be quite a deep hole it made there.
Posted by: Baltic Dec 22 2004, 05:55 PM
Great pics! Christmas is early this year!
Tom
Posted by: djellison Dec 22 2004, 06:44 PM
'technically' - I've got what I asked for for my Birthday - a colour mosaic of the heatshield - but I was expecting more YOU'VE GOT 6 HRS ROVER DRIVERS. I TURN 26 ON THE 23RD.
Doug
Posted by: Decepticon Dec 22 2004, 07:03 PM
Now I know what the Mars Polar Lander looks like. 
Posted by: azstrummer Dec 22 2004, 07:24 PM
Happy birthday to Doug.......
Posted by: Gray Dec 22 2004, 07:53 PM
That image of the heat shield is another candidate for your book, Doug. It's like an image from star Wars, only for real! 
I hope your birhday wishes come true. Have a good one.
Posted by: Baltic Dec 22 2004, 09:06 PM
YOU'VE GOT 6 HRS ROVER DRIVERS. I TURN 26 ON THE 23RD.It's still time!
Hope, you get what you want!I turn 36 in January, and I'm hoping Huygens will make my day!
(Actually it's not the same day.)Last year I was hoping for a good christmas present vom Beagle-2 (never arrived, you know
) and a good birthday present from MER ... I got SO MUCH for my birthday and the year after! Tom
Posted by: azstrummer Dec 22 2004, 10:16 PM
Great 3d heatshield pic from Marsunearthed.com:
http://www.marsunearthed.com/Opportunity/OpportunityGlyphs/Opportunity90_3D/Opportunity90_3D.htm
Posted by: djellison Dec 22 2004, 11:02 PM
http://www.marsunearthed.com/Opportunity/OpportunityGlyphs/Opportunity90_3D/Opportunity90_3D.htm
Hmm - those ones done without any TLC just dont work for me at all. I dont get much perception if any with that.
..some time passes...
THAT'S better
Doug
Posted by: Mode5 Dec 23 2004, 04:14 AM
Your work is superb. Thank you Doug.
It would be interesting to compare the amount of accumulated dust to that on the rovers. Too bad it looks wobbly and is a hazard.
Posted by: CosmicRocker Dec 23 2004, 04:24 AM
Outstanding images...They really allow us to better appreciate the scene.
There's one thing I don't understand from an earlier comment, though. Why would it be so dangerous to closely approach the large piece of the shield? It would seem that they took much greater risks with Opportunity while inside Endurance crater. I would have thought they'd want to get close enough to at least take some MIs of the shield's surface.
Posted by: azstrummer Dec 23 2004, 04:31 AM
Boy, do I agree with you. They seem to have really precise control over positioning of the rovers except on big slopes and in deep sand. They can get as close as they want. It's not like the thing is going to attack them. Now the Martian with the raygun behind it........
Posted by: lyford Dec 23 2004, 05:50 AM
Awesome color mosaic - and Happy Birthday!
Posted by: CosmicRocker Dec 23 2004, 07:17 AM
It really does look as if it impacted sideways, but the fact that it is so bent up suggests it's compressive strength on impact was less than the compressive strength of the surface it encountered.
If this area is anything like what Opportunity has seen elsewhere on the plains, the soil is only a few centimeters thick, at the most. Under the soil is bedrock. I think the weaker heat shield deformed when it landed, absorbing much of the energy, and creating a crater no more than 10-30 cm deep.
This is going to be a pretty interesting site to investigate.
Posted by: Baltic Dec 23 2004, 07:25 AM
Happy Birthday, Doug!
Tom
Posted by: Stu Dec 23 2004, 08:07 AM
Happy Birthday Doug!
In honour of all your outstanding work, I vote we - unofficially! - christen the crater made by the impacting heatshield "Doug's Birthday Crater".
Anyone second that?
Stu
Posted by: OWW Dec 23 2004, 08:28 AM
How about 'Doug's Dig' for that trench? Happy Birthday.
Posted by: djellison Dec 23 2004, 08:59 AM
My point was - you dont want to go up to it when that mylar might flap around and hit the PMA. Worse -touch it with the IDD and it falls over. It could happen. Quite how a 40kg off piece of heatsheild has ended up on it's end is anyones guess - and it looks quite precarious to me. Especially when there' a nice big bit sat flat on the ground that can do no harm to anyone
Thanks for the Birthday wishes chaps
Doug
(PS - How about 'Dougs Ditch' ? )
Posted by: ilbasso Dec 23 2004, 07:17 PM
Since two of the three craters that Oppy has studied so far (Eagle, Fram, Endurance) began with E, why not simply and elegantly name this crater "Ellison"?
Posted by: Stu Dec 23 2004, 08:28 PM
...because then people over here in the UK will think it was named after the ex-Brookside "actress", Jennifer Ellison, who couldn't act her way out of a crisp packet, and is best known for rather, er, revealing photo-shoots in lads mags...
Think we're better off with the word "Doug" in the title.
Posted by: Pando Dec 23 2004, 09:18 PM
HAVE A WONDERFUL BIRTHDAY, DOUG!!!
Posted by: OWW Dec 23 2004, 09:25 PM
What happened here? Bouncing airbags, bouncing heatshields?
Posted by: OWW Dec 23 2004, 09:27 PM
The heatshield from a different perspective:
Posted by: akuo Dec 23 2004, 11:15 PM
One more navcam picture.
Not much of a hole at all. Oppy could dig something like that with its wheels.
Posted by: djellison Dec 23 2004, 11:18 PM
Ahh - see, there's an 'Ellison' Crater on the moon. (really - it's just around the far side - google for it )
Doug
Posted by: Pando Dec 23 2004, 11:22 PM
I think we're not seeing much of the hole because of the bedrock so close to the surface. There's probably just a few inches of soil and blueberries, that's pretty much it. The heatshield was fairly light, and when it hit the ground looks like the aluminum foil insert broke away from the rest... Sort of like tossing a pie plate to a concrete covered by a thin layer of sand...
That's a bit different from the Genesis crash, which landed into a fairly soft soil (mud).
Posted by: djellison Dec 23 2004, 11:39 PM
Happy birthday to me...
Happy birthday, to me...
Happy birthday dear meeeeeee...
Happy birthday to me 
(Went to the a local zoo that is big on Primates - they're great to sit and watch. Somehow, nice though lizards and giraffes and elephants and rhinos are - they dont play to the camera like these guys - that was the best pic I took today )
I got what I wanted A book on Donald Campbell, Jeremy Clarksons new book, a panorama of the heatshield - AND - we went to see the monkeys. Doesnt take much to make this 26 year old happy ;P Just $850M of rover and a couple of monkeys.
Doug
Posted by: MizarKey Dec 24 2004, 12:00 AM
Happy birthday Doug, didn't realize you were such a pup (26? ain't nothin'... )
I was trying to get the 3d's I did up, but from work I don't have any ftp space to access, damn Yahoo pictures is mostly useless...
I disagree with Akuo's assessment that Oppy could dig something similar with its wheels...in the 3d images the crater looks a bit deeper than the wheels. I hope we get a lot of close up shots of the crater.
Anyway, I've got a link to my 3d images, though they aren't much different than the ones Doug posted so you're ok if you pass...
http://pg.photos.yahoo.com/ph/mizarkey/album?.dir=7dcf&.src=ph&store=&prodid=&.done=http%3a//pg.photos.yahoo.com/ph/mizarkey/my_photos
Eric P / MizarKey
Posted by: Sunspot Dec 24 2004, 12:10 AM
Hope you had a nice Birthday Doug
I like this image from the navcam...the small dunes look like snakes heading towards the rim of Endurance.
Posted by: lyford Dec 24 2004, 01:22 AM
At least it isn't 850 million dollars worth of monkeys!
Happy Birthday and thanks for all the great pics on this board.
Posted by: BruceMoomaw Dec 24 2004, 01:40 AM
It's been very clear from the start of MER-B's explorations on Meridiani Plain that the plain is a very thin layer of basalt sand mixed with Blueberries, spread over a flat sheet of underlying sedimentary bedrock. What's happening -- as Ray Arvidson predicted in advance from MGS' orbital observations -- is that the sand has blown in from other places and is slowly eroding away the rock layer from the top down, powderizing the soft matrix rock and leaving a residue of Blueberries mixed with the immigrant sand. But of course once the thickness of the sand layer builds up beyond a certain point it stops the erosion process until some of the built-up sand blows back out of Meridiani and the erosion resumes -- so the overlying sand/Blueberry layer will ALWAYS be very thin. (I wonder how many Blueberries are mixed with the sand that's blown all the way through Meridiani and out the downwind side?)
That circular impact mark makes it clear that the heat shield came down flat on the surface and then bounced -- whereas the Genesis capsule, which was wobbling greatly during its fall, apparently came down on one edge.
Posted by: Stu Dec 24 2004, 10:24 AM
Finally the truth is out - Oppy landed on Arrakis.
Those aren't small dunes, they're sandworms...!
Posted by: djellison Dec 24 2004, 10:51 AM
Hands up if you've gone to the top of your stairs and taken the heatshielf from the MPF Hotwheels pack and dropped it to see if it always lands the same way
Warning. Castor Sugar+Drinking Chocolat experimentation may follow
Doug
Posted by: djellison Dec 24 2004, 11:29 AM
I assume this will be part of a 3 x 2 mosaic or something like that within the next 24 hrs or so.
I'm very much AFK from tomorrow thru to probably Dec 31st - so unless the rest of that mosaic comes down tonight - then it'll have to wait
Doug
Posted by: Decepticon Dec 24 2004, 01:59 PM
In what image does it show Opps heading after the heat sheild observations?
Posted by: djellison Dec 24 2004, 02:29 PM
This sort of direction
Due south basically
Doug
Posted by: BruceMoomaw Dec 24 2004, 04:46 PM
Latest shot of the heatshield is at http://qt.exploratorium.edu/mars/opportunity/pancam/2004-12-24/1P157123523EFF40A3P2359L7M1.JPG . The sun's reflection off the interior is so bright that it's saturated a large part of the photo; but one can clearly see little shattered bits of the heatshield scattered around the landing area.
Posted by: djellison Dec 24 2004, 05:07 PM
I wonder what one of those springs would fetch on Ebay
Doug
Posted by: Pando Dec 24 2004, 05:13 PM
Doug
You mean *after* someone brings them back from Mars?
Posted by: djellison Dec 24 2004, 05:25 PM
'Buyer Collects'
Actually - didnt the RSA sell one of its lunakhod rovers for a few thousand $'s - with the 'Buyer Collects' proviso?
Doug
Posted by: Pando Dec 24 2004, 05:44 PM
In that case the heck with the spring, go with the whole rover
Posted by: djellison Dec 25 2004, 08:41 AM
HAPPY CHRISTMAS EVERYONE!!!
Now sod off and eat Turkey
Doug
Posted by: volcanopele Dec 25 2004, 09:43 PM
Turkey not done yet :mad: But look at all that junk strewn around. I remember when there were some cranks thinking they were seeing machine parts and springs in the Spirit images and well, there are some real springs How big is that large one on the lower left side of the main heat shield part?
Posted by: cassioli Dec 26 2004, 05:24 PM
I'm no more reading this forum since several months... <:-)
Your images are very interesting! Maybe Opportunity took enough pictures so somebody can produce 2 color photos of the heatshield taken from close angles, so I could combine them in a 3d-color-anaglyph? It would be cool!
I also would like to build a little animation of the heatshield: are there enough different angles pictures to allow this? Can you give the links, or just link the thumbnails?
BTW, what is the "Genesis" you are talking about?
Posted by: Analyst Dec 26 2004, 06:43 PM
"Genesis" ist the poor little solar wind sample return spacecraft that crashed into the Utah desert in September 2004. BTW, is there any news on the sample quality yet?
Analyst
Posted by: pioneer Dec 26 2004, 09:54 PM
I heard some samples were salvagable, but I haven't heard about any results from them.
Posted by: BruceMoomaw Dec 26 2004, 11:32 PM
Opinions seem to vary on whether the Genesis samples are scientifically retrievable. The team itself is insisting that many of the collectors for oxygen and nitrogen isotopes in the solar wind -- the top two science goals of the mission, by far -- are indeed retrievable, and that the same may be true of many of the lesser goals (such as noble gas analysis). Others -- such as SpaceDaily's professional curmudgeon Jeffrey Bell -- say that, since the solar wind atoms are embedded only 1/50 of a micron deep in the collector plates (that's less than 1 millionth of an inch) and the latter were exposed to atmosphere, humidity and dust, no scientist in his right mind will trust the results. However, I've talked personally with Donald Brownlee -- the PI for the Stardust comet-dust retrieval mission -- and he thinks that it may very well be possible to adequately clean the top surfaces of the collector plates of contamination without removing such shallowly embedded solar wind atoms; as he points out, anyone who washes a glass window with a non-abrasive substance routinely does just that. So, until I learn more, I reserve judgment.
Brownless, by the way, also says that an examination of the construction records for the Stardust capsule make it pretty certain that the upside-down parachute switch error in the Genesis capsule has not been repeated for the Stardust capsule -- but he also says that, since the dust grains in Stardust are embedded 1 to several cm deep in a sheet of relatively nonbrittle aerogel, they are more likely to come through a crash in scientifically acceptable shape, unless the capsule crashes onto the salt flats after the latter have been recently rained on. However, finding and retrieving the capsule quickly would be vital -- and the Stardust capsule will land at night.
Posted by: tedstryk Dec 27 2004, 04:23 AM
This is all good to hear. After reading his recent article, my suggestion to Mr. Bell is that he seek therapy, as he seems generally angry at the world. However, his concerns are often not born out by more reputable scientists. My suggestion is that he sometimes look on the bright side of things, or he find some private place to go and be really, really sad where he can't bother anyone else.
Posted by: jamescanvin Dec 27 2004, 12:01 PM
That picture is a great Christmas present Doug. Thanks, how did you know what I wanted!
James
Posted by: BruceMoomaw Dec 27 2004, 02:10 PM
In my own experience, Bell is right about 80-90% of the time. ANYONE who has to deal habitually with NASA naturally turns into a cynic (including Reagan's science advisor George Keyworth, who called it "the only governmental agency which lies not just sometimes but most of the time"). As for Genesis, we have yet to see who's really correct.
Posted by: BruceMoomaw Dec 27 2004, 02:12 PM
Latest shots fo the heatshield at http://qt.exploratorium.edu/mars/opportunity/pancam/2004-12-27/ . Is that white sheet which overlays the biggest fragment the actual heat-resistant cloth layer? If so, it came through Martian entry pristine-looking, with no visible sign of charring.
Also some nice closeups of the actual impact crater, such as http://qt.exploratorium.edu/mars/opportunity/pancam/2004-12-27/1P157306770EFF40A3P2360L4M1.JPG -- confirming again that the shield, despite coming down fast enough to shatter itself, barely punched into the solid rock layer covered by just a few cm of sand -- and some more of the second-largest shield fragment, such as http://qt.exploratorium.edu/mars/opportunity/pancam/2004-12-27/1P157307401EFF40A3P2360L7M1.JPG .
Posted by: Sunspot Dec 27 2004, 03:25 PM
Do you think it would be safe enough to drive the rover into the "crater"? Perhaps they could perform a trenching operation inside the impacted area to see how far down the bedrock is.
Looking at the heatshield in it's current state.....I think it may literally be "inside out"... the shiny layer we see was part of an insulating layer on the inside of the heatshield.
You can just make out a kind of rough textured surface on the other side which I think might be the abaltive material on the front of the heatshield.
It's a little easier to see in this image:
Posted by: ilbasso Dec 27 2004, 03:41 PM
Anybody have a guess at the heatshield's approximate speed when it impacted?
Going back through the timeline, it looks like the heatshield separates from the backshell at somewhere between 25,000 and 30,000 feet in alitutde, 20 seconds after chute deployment (the chute deploys at 30,000 feet and 1,000 mph). I wonder what the terminal velocity is for such an object...relatively flat and light - how much would wind resistance have slowed it down even though there is less air than on earth, but counteracted somewhat by lower gravity? Genesis came in pretty hot and didn't even have the benefit of a parachute, but it impacted at "only" 200 mph.
I agree that it looks like the big piece is turned inside-out. I would bet that the thermal blankets go on the inside. The schematic on the MER website also indicates that there is a "radar absorber" in the heatshield - is that part of the blanket's function?
Piece "B" looks like it has some charred surfaces readily visible.
Posted by: BruceMoomaw Dec 28 2004, 01:27 AM
Yes, I have since been taken to the woodshed by another member of my Planetary Science webgroup (who shall remain nameless) regarding my misinterpretation of what I was looking at:
"The 'white' sheet is the base layer of a series of sheets of material,
capped by a reflective mylar layer - the innermost part of a
multi-layer thermal protection system. This consists of a structural
frame, an outside ablative layer of what Gary Allen advises is
ground-up cork and resin binder, and an inner thermal blanket to stop
residual heat getting through to the rover.
"What is perhaps confusing you is that the piece of the wreckage that
is standing up on its side has been almost flipped inside out.
" http://www.lyle.org/~markoff/processed/1P157305976EFF40A3P2578L234567M1.JPG
"The dark 'knobbly' material is the heated and partly ablated TPS. The
broken edge at the left shows the paler-brown surface that has been
altered by re-entry heat compared to the thicker dark unaltered
material. You can see parts of the mylar layer, and the underlying
white blanket that has been everted over it."
Well, that's what I get for not actually looking up the structure of the heat shield -- I was thinking vaguely of the flexible entry-thermal blankets that cover those parts of the Shuttle exposed to minimum heating.
Posted by: BruceMoomaw Dec 28 2004, 01:40 AM
Has the rover rolled right up to one of the heat shield fragments? I find it impossible to interpret the little thingie at the top of this Forward Hazcam image any other way: http://qt.exploratorium.edu/mars/opportunity/forward_hazcam/2004-12-27/1F132988527ESF06FRR2761R0M1.JPG .
Also, what's with the spot on the left front wheel where some of the aluminum tread is missing? I know that there was one patch on each wheel where it was deliberately omittted -- but this missing patch seems irregularly bordered, and there's what looks like a crack leading away from one of its edges.
Posted by: mhoward Dec 28 2004, 02:18 AM
The image in question is actually from Sol 54, or thereabouts; you're looking at the egress ramp on the lander and part of an airbag. I know, it threw me for a minute, too! I guess Oppy is clearing out its memory banks for some reason.
Posted by: Mode5 Dec 28 2004, 02:39 AM
The tread mark track at the 11 o'clock position reveals they may have gone a little too close to the wreckage. It gives the appearance that at least one side became slightly elevated into the air.
There is a small amount of dirt in a pile at the base of the debris as if the wreckages were pushed further into the ground. I wonder if this is from a possible collision with the rover or if was always present?
I don't see anything wrong with the wheel. I hope they re-evaluate the risk vs. reward at the site. There are a number of sharp elevated angles which do not resemble type of rock. Dragging a wheel is one thing but dragging a piece of debris around would be a terrible way for this rover to go out.
In re:
http://qt.exploratorium.edu/mars/opportunity/forward_hazcam/2004-12-27/1F132988527ESF06FRR2761R0M1.JPG
Posted by: Pando Dec 28 2004, 03:09 AM
This image was made in Eagle crater next to the lander platform, something like 9 months ago. It doesn't show any 'wreckage' of any kind.
Also, the wheel tread has a section where it was attached to the landing platform. That section is the one visible on the left front wheel in that image.
I don't think any of the heatshield debris poses any danger to the rover, unless it actually collides with a large piece head-on... Nevertheless I doubt they will attempt to drive the rover over the large pieces of course
They are planning to do some IDD work with the soil that was disturbed by the heatshield crash. Also, they may do some work with the rock found nearby that resembles the 'Bounce Rock' they found close to Eagle crater.
Posted by: Pando Dec 28 2004, 03:34 AM
Also, this image shows the assembly -- it does look like it has turned inside out. Notice the shiny foil-like material on the inside.
What most likely happened was that the shield came down nose first, the nose hit the ground and edges came down some milliseconds later. The nose shot back up, tearning the saucer apart and turning it inside out, and a sector broke away and landed nearby. And as a result there is a flat crater where it did a nice belly-flop.
Posted by: mhoward Dec 28 2004, 03:50 AM
And not to beat this subject to death, but in case anyone was wondering, the mark on the ground is the start of a trench that Oppy dug, on purpose. Again, months ago.
Posted by: BruceMoomaw Dec 28 2004, 09:10 AM
Oog. That same guy on the Planetary Sciences website (curse him!) has pointed out that the date of that Hazcam photo is incorporated into its ID number -- and that it is indeed one of the rover's earliest photos, disgorged from the back recesses of its memory at this late date. (Which makes one wonder how much else is still stuffed back there.) The latest Navcam shots, however, do confirm that the rover is gradually making its way closer.
(It's also a lot easier to understand how the heat shield could have turned itself inside-out on impact when you consider how shallow a cone it actually is.)
Posted by: Sunspot Dec 28 2004, 10:34 AM
No time to stop.............. they've driven past the heatshield.
http://qt.exploratorium.edu/mars/opportunity/navcam/2004-12-28/1N157490512EFF40AJP0645L0M1.JPG
...fairly close to the other fragment now:
http://qt.exploratorium.edu/mars/opportunity/navcam/2004-12-28/1N157490564EFF40AJP0645R0M1.JPG
Posted by: mhoward Dec 28 2004, 04:48 PM
I love that you can see Endurance Crater in the background, and even see the rover's tracks all the way to the horizon. Nice.
Posted by: ilbasso Dec 28 2004, 05:40 PM
Looking at the new view of the main shield fragment, I can see why they are passing it by. I would bet that those blankets could blow around in the wind. Not something you'd want to get your antennas and camera masts stuck in!
Posted by: dot.dk Dec 28 2004, 05:46 PM
Can't see if the fragment has the protective side of the shield upwards.
http://qt.exploratorium.edu/mars/opportunity/navcam/2004-12-28/1N157490564EFF40AJP0645R0M1.JPG
If it has, then they most likely will do some MI work on it
Posted by: ilbasso Dec 28 2004, 06:43 PM
Looks to me like this piece is twisted. The fragment toward the top/left of the frame looks charred and is convex. The fragment on the right looks concave and appears to have some of the insulating blanket still attached -- the blanket also appears to be caught on/wrapped around the piece that runs across the bottom of the picture - which I think is a small section of the large ring that circles the heatshield and attaches it to the upper part of the aeroshell.
Posted by: Pando Dec 28 2004, 08:02 PM
The material is fairly stiff, I doubt there is anything to blow around in the wind, especially in the thin Martian atmosphere. A parachute would be a different story of course, but the main reason they're driving around the big fragment is that the smaller fragment's scorched outer layer is easily accessible for IDD work. They of course are also imaging the big fragment in different angles.
Posted by: Mode5 Dec 29 2004, 08:34 AM
Eagle Crater! Egads, thanks for the correction Pando.
Edit:
I should have read Mhowards post too. Whoops! 
Posted by: dot.dk Dec 29 2004, 11:07 AM
Looks like they are approaching the fragment 
Posted by: Sunspot Dec 29 2004, 11:13 AM
Looks like burnt toast ..... kind of crispy.
Posted by: mhoward Dec 29 2004, 02:27 PM
In 3D:
Posted by: mhoward Dec 29 2004, 02:28 PM
Pancam closeup anaglyph:
http://img93.exs.cx/my.php?loc=img93&image=1p157576775an1ny.jpg
Posted by: remcook Dec 29 2004, 02:32 PM
belated happy birthday doug! 
by the way:
new route map available:
http://www.spaceflightnow.com/mars/mera/041228heatshield.html
Posted by: mhoward Dec 29 2004, 04:32 PM
Whoah! Color.
http://img55.exs.cx/my.php?loc=img55&image=1p157576671fcl2l5l71lj.jpg
Posted by: alan Dec 29 2004, 06:16 PM
The ablative material looks like scorched carpet
Posted by: Pando Dec 29 2004, 07:28 PM
Latest: There are indications that there is a possible dust storm developing. The power levels have dropped quite dramatically at around Sol 330 for Opportunity and is somewhat worrisome. At Gusev things are trending similarly although it's a Sol or so later. This is getting interesting as it may even mean a global dust storm.
Posted by: dot.dk Dec 29 2004, 07:38 PM
Uh ohhh
How much are the drop in power?
Posted by: ilbasso Dec 29 2004, 07:55 PM
Interesting mosaic of the heatshield impact crater on the JPL MER site (excerpted below). It certainly looks as though the heatshield hit almost completely flat. I did some very rough calculations on the terminal velocity of the heatshield in Mars' atmosphere (assuming a rough surface area of 10.5 m^2 and a mass of 78 kg)...it looks like the terminal velocity at Mars surface for such an object would be on the order of 120 mph. Didn't make much of a dent, did it? -- but the energy sure bent the hell out of the heatshield!!
Posted by: BruceMoomaw Dec 30 2004, 02:52 AM
It's hardly surprising that it came down upright -- it was, after all, shaped so that the airflow itself would stabilize the lander during entry. As for its barely penetrating the surface: I repeat that this entire plain, for hundreds of km, is apparently just a layer of basalt sand a few cm thick covering a flat surface of soft rock that's being gradually eroded away by the sand blowing across it.
Posted by: dot.dk Dec 30 2004, 11:19 AM
Up close and personal 
Posted by: mhoward Dec 30 2004, 03:00 PM
Real up close and personal!
http://img53.exs.cx/my.php?loc=img53&image=1n157664885ana1ua.jpg
Posted by: MizarKey Dec 30 2004, 04:03 PM
http://img53.exs.cx/my.php?loc=img53&image=1n157664885ana1ua.jpg
MHoward, one of the first things I read when I wanted try an make 3d anaglyphs is that you need to crop the parts of the images that don't overlap as it distracts the eyes and makes it harder to see the 3d effect.
I'm not sure which software package you're using, but here's a link to the tutorial I used for Adobe...http://www.scec.org/geowall/makeanaglyph.html
I love the fact that we can make anaglyphs from the rover images...here's one from http://members.aol.com/mizarkey/Sol2883d.jpg
Eric P / MizarKey
Posted by: mhoward Dec 30 2004, 05:27 PM
I'm not sure which software package you're using, but here's a link to the tutorial I used for Adobe...http://www.scec.org/geowall/makeanaglyph.html
I love the fact that we can make anaglyphs from the rover images...here's one from http://members.aol.com/mizarkey/Sol2883d.jpg
Eric P / MizarKey
It's a long story on why I do the anaglyphs that way... suffice it to say I was not doing any image editing but was only trying to present a "first look" as the images became availabe. I will discontinue posting these here. Thanks for the feedback.
Edit: To be clear, I automate anaglyph generation, that's why I wasn't doing any "image editing". I will incorporate your suggestion in future versions, though, if practical, so thanks.
Posted by: MizarKey Dec 30 2004, 11:20 PM
Hey, does it look like some wetness precipitated off the shield onto the sand below causing it to compact...towards the upper left side of the image?
It reminds me of the 'mud' around both landers, though, with the landers it was the airbags being drug across that left the wet like residue.
It could be that frost has formed from time to time and if the conditions are right melts down the shield to drip onto the dust below???
Eric P / MizarKey
Posted by: ilbasso Dec 31 2004, 02:13 AM
Interesting! I thought that actively blowing dust might also be an explanation, but the pattern is same in both the left and right images.
When the shield fragment plopped down, might it have blown some of the dust out of the way? Even so, it would be hard to explain the boundary that's so clear in the lower part of the image. There are some streaks in the upper part of the image that seem to streak away from the middle of the image.
Posted by: BruceMoomaw Dec 31 2004, 03:33 AM
I suspect that the "muddy"-looking surface we're seeing there (there's an identical area on the near edge of the landing impact crater in its photos) is really just an area where the shield's impact crushed and powderized the Blueberries into fine hematite dust -- which would, by the way, also have turned red. (The color photos of the shield site show just such red coloration in the areas where the shield hit the surface -- just as we see when the RAT grinds up Blueberries into red powder.)
Posted by: djellison Dec 31 2004, 08:47 PM
Six frames of L7 imagery
Doug
Posted by: Sunspot Jan 1 2005, 01:39 PM
MI pictures of the heatshield are in:
http://qt.exploratorium.edu/mars/opportunity/micro_imager/2005-01-01/
Posted by: Sunspot Jan 1 2005, 01:55 PM
From space.com
http://www.space.com/missionlaunches/roverdebris_041231.html
"We have circled around to a secondary debris site we are calling the ‘flank piece’", noted Christine Szalai, JPL’s leader of the heat shield observations team. "These are some pieces that broke off of the main heat shield after impact," she told SPACE.com.
Szalai said that a set of "interesting targets" have been identified – targets to home in on with the rover’s Microscopic Imager for carrying out fracture cross-section looks this weekend.
"This data will hopefully tell us the char depth through the thickness of the thermal protection system material. After we are done with this investigation, we are going to continue the spiral to survey the main heat shield and come in close to obtain more imaging data," Szalai explained.
Following its foray into the swath of discarded hardware, where next for Opportunity?
Steve Squyres, lead scientist for the Mars Exploration Rover program from Cornell University, said the robot has a very tough next assignment. The driving objective for Opportunity is etched terrain to the south of Endurance crater – a large impact feature in which the robot recently completed six months of rewarding science work.
"The distance we'll have to cover to reach the etched terrain is something like three kilometers [some two miles], so it's a very aggressive goal. If we can reach the etched terrain, we expect that exploring it will take a substantial amount of effort and time," Squyres told SPACE.com.
"We don't currently know whether or not it will be possible to traverse a significant distance into the etched terrain. From orbit it appears to be pretty rugged stuff, so it may represent an impenetrable barrier to further southward exploration. We'll see when we get there," Squyres advised.
On the far side of that etched terrain is the huge Victoria crater. Chances of the rover reaching that geological paradise of a hole in the ground "are probably not good," Squyres said. "But if we did somehow manage to make it across the etched terrain, Victoria would be a very exciting next objective," he added.
Squyres said that next week, he will discuss "an interesting intermediate goal" -- something on the path from the heat shield to the etched terrain -- at a Mars Exploration Rover press briefing.
Posted by: CosmicRocker Jan 1 2005, 05:15 PM
Let's hope he's speaking of Monday's briefing.
Posted by: Pando Jan 1 2005, 10:24 PM
They may do some crater-hopping not only for the science value of it, but also for the favorable tilt they may experience on the slopes, especially during dust storms...
Posted by: djellison Jan 2 2005, 12:48 AM
One assumes they mean vostok crater ?
Doug
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