It seems that most quote :



As the source for the 1955 date. In that paper, they simply say:

Actually - smallish, metalic asteroids don't make for an easy entry - they tend to air-burst at a few km up.

If, say, a 10m iron asteroid was able to impact (7.5km/sec being the impact speed) you're talking about a 100x25m crater.
http://www.convertalot.com/asteroid_impact_calculator.html

Or much bigger according to
http://impact.ese.ic.ac.uk/cgi-bin/crater....&tdens=2500

A >10km/s impact is more likely - and that's more likely to air-burst.

http://simulator.down2earth.eu/ is also fun.

The lithbraking method of Earth arrival is not one I would recommend or support.

Given that it took a very large MOI burn to get IN to Mercury orbit - I would have thought it's fairly obvious that they're not getting out again.

Looks to me like they're planning something around 350-400 kbps - which would be spectacular from Jupiter. Can't find a data rate directly, but can infer it from the 1.4Gb in an 8hr pass.

The redesign of TPS's website.

What's the ob ID's for that one? It's a beauty.

If current to an arm were to find its way to a steering actuator - that would be a symptom of something pretty catastrophic. I doubt it.

Seriously guys - that's not what's happened here.

There's no reason to suggest any current went to the wheel motor - it didn't turn - and there are brakes on the wheel drive motors anyway that would have to be disengaged I believe.

Take the combo of moving the arm around (quite a lump on the end of a long stick), strong winds with large solar arrays, and on a rocky slope, it's easy to see how the rover could just nudge ever so slightly.

Indeed - up at the summit of Husband Hill, Craig Covault's article about 'Rocky Martian High' talks about concerns in moving the arm whilst on a slope that might cause the rover to move slightly.

That's not a great place to pull the total number of images taken. That's the number of images taken,downlinked, piped thru the raw processing pipeline and uploaded to the JPL image page.

Oh no, I distinctly remember the Deep Impact impact being washing machine sized.

They don't appreciably deform (especially under Mars gravity where each wheel's loading is only about 10kg equiv) - but they do squish into the ground, you're right.

Scooter - as for rights issues.....that's your model, you made it and so own the rights to it, but I would drop JPL media relations a courtesy email just to make sure you're not stepping in any hot water if you try to profit from it, given Caltech's unique relationship between NASA and JPL, and the legal authority they have over the 'likeness' of the rover itself.

And of course, that depends where you're definition of 'Enough' is.

Well - there's a couple of things I'd still tweak, and I'm still not convinced by the wheels - but yeah...

that's pretty awesome

I can't really believe I'm saying this. They still look reflective. I can see the rocks in the soil infront of the wheels reflected in them.

For whatever reason - they simply look reflective. You need to quit the 'dirty' idea - and re-render them as near flat matt black. Go look at the amount of influence the bright blue puppy-training paper has on the color of the wheels back at KSC. Almost zero. The dust also tends to slip and slide off very easily. Till you dump the 'dirty' color, I think it'll continue to look shiny and reflective.

Got to say - those wheels still look very very shiny. They're not flat black enough by far ( and the chrome metal hold-down bold is still on each wheel )

Yeah - the wheels still look mighty shiny, however you got there. It needs to be a far more matt with a very soft specularity to it. Getting there, but not quite

Another thing worth doing.... take all the layers that make the rover - add a tiny bit of noise, and then soften it by about a third of a pixel, just so the feel, the inherent texture of the rendered image better matches the pancam mosaic.

Shiny - but not reflective. And infact, after driving a short distance on Mars, that shine is pretty much gone.

http://marsrover.nasa.gov/gallery/spacecra...mer1_021003.jpg
http://marsrover.nasa.gov/gallery/spacecra...s/tworovers.jpg
http://www.nasa.gov/externalflash/ksc_45th/hi-resjpgs/24.jpg

You're definitely getting there. The black wheel tread is still reflective rather that just a soft muted shiny, and I'd say you could tone down the saturation of your fill light from BEIGE to 'mocha..extra milk please' - if nothing else to help the rover just stand out a bit more.

Great work though, nice progress. See...told you it would sit well in a real image.

Having worked in the industry for 12 years....I can tell you - there is no other kind. I'm giving you the hardest time I can, because that's the most appropriate and realistic feedback to get...honestly

These shadows - http://www.unmannedspaceflight.com/index.p...st&id=26549 - are a little soft, because it's late in the day. Most large color pans are taken between about 11am and 2pm - so near 'noon' like lighting. Bright, sharp etc. Basically, you need to balance that sun light and the backfill diffuse dusting light to get both the right total brightness AND contrast between the illuminated parts and shadowed parts. It'll make you cry to see all your amazing rover electronics box stuff get hidden into shadow, but that's where it's going to end up unless you do late in the day images.

So the only problem with the rover on the Spirit panorama is the shadowing. You're still rendering it like it's in a big open room with loads of lighting etc etc. On Mars there are two lighting sources... the sun (and because we're at 1.5AU, shadows are a little sharper) and the diffuse illumination from the sky (which backfills the shadows and is the main source of the beige tint to everything). You need to get those shadows right to make the rover look like it belongs on the surface.

Take your cue from the few rocks big enough to be casting shadows on that image.


Also - you have the wheels being quite shiny and reflective. They have a slight, very diffuse specularity to them, but almost no reflectivity. I'd dump the reflectivity all together and just have a specularity - you'll save some render time at the same time.

I found the EPOXI camera temp plots that went on the PDS fascinating. They only cover 2007-11, but they're interesting none the less.

I know that the headers for every image in the PDS have a swathe of temperature readings within them.




I agree though - a verbose temp sensor dump would be fascinating for MER (and Phoenix)

Viking did this very well

http://www-k12.atmos.washington.edu/k12/re...ation/data.html

Actually - you could put the rover at almost any angle you wanted within a panorama - you just have to put it in the right place to match that angle (or vice versa) . As for resolution - yes, the Pancam images are low res compared to what you're doing....so you just render at a resolution to match the background.

This has been done before : http://marsrovers.jpl.nasa.gov/gallery/spe...Effects/spirit/ and http://marsrovers.jpl.nasa.gov/gallery/spe...ts/opportunity/

This is where experience really kicks in - you need to start rendering multiple passes - a shadow pass, an AO pass, a diffuse pass etc etc - then you recomp them all together in post.

I can totally understand if you don't want to go to all that effort - but that doesn't mean it's not possible.