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UK Space budget is an embarrasment. I've written to every MP I've ever had, two Prime Ministers, and a Science Minister asking why our spending per capita is a tiny percentage of that of other developed worlds - and not once had a valid answer.

With the knowledge base and resources in this country - we should be regularly having MAJOR involvement in space exploration - but no.

Hopefully - this is a small step forwards!

Of course - Aurora is a flawed plan anyway - essentialyl paying to develop a MER scope rover when our friends the other side of the pond have already developed a beautiful working MER! Seems stupid really.

Doug

On a scientific basis - that's FAR from true.

Doug

MOC images dont really have an 'exposure' per se.

It's not a digital camera as you or I would know it.

Where as a typical camera sensor is an array of say, 2000 x 1600 ish pixels - the MOC camera is just a line of 2048 pixels.

"Huh"

Exactly - take a picture with that and you'd get a 2048 x 1 pixel image.

BUT - as the spacecraft orbits the planet - the view of that 2048 x 1 pixel moves.  So - take one picture every, say, 0.7 milliseconds - and stack them on top of each other - and you get the second dimension of the image    So in essence - you can have a 2048 x anynumber-until-the-moc-buffer-is-full

The techinque is known as 'push broom' - as the camera moving over the surface is a bit like a broom moving along a floor.

You can see the line integration time in the image info for each MOC image - and typically - it's 0.7msec (0.0007 seconds) - so - in one second we'd have 1428 lines recorded.  At about 1.5 metres per line - thats something like 2.1km per second. So as you can see - a moc image is take VERY quickly

'What the hell's a ROTO?"

Roll only targetted observation.  But rolling the spacecraft left or right of the usual face down attitude - you can take pictures off to one side.

"What the hell's CPROTO"

I believe thats compensated pitch and roll targetted obs. or something like that - where no only do they roll to one side or the other but they pitch the spacecraft to make the apparant speed of the pushbroom along the surface seem slower - so - instead of recording 2.1km in a second - you might record only 700 metres - giving you much higher resolution in the direction of travel

So - as you can see - a Moc image doesnt really have an 'exposure' - but each individual line has an integration time - usually about 0.7 msec.

And here endeth doug's very bad guide to the MOC

Doug

Extra weight - but still a HUGE ammount of weight saving over any other solution. The sort of weight saving that makes the difference between a mission being feasable - and a mission not being feasable.

Doug

On a 6 month flight to mars - cryogenic storage of H2 would have about 15% boil off. The point of H2 is that it's so very very light. You get a hell of a lot of moles of H2 in, say, 100kg, compared to just about anything else.

Doug

The themis data is presented MUCH better than MOC data - and is simply point and click till you find the area you want...
http://themis-data.asu.edu/mars-bin/mar … OOM]Themis Search Page

I ended up finding these images

http://themis-data.asu.edu/img/V0741600 … 16001.html  35m res multi-spectral - the colour image shows that we can expect the terrain to become a little more typically martian as we get closer to Victoria

http://themis-data.asu.edu/img/V0630500 … 05001.html  18m res mono-spectral image - this is the one I used in my map - Victoria is near the bottom - with Endurance on a bearing of about 355 degrees

I also found that the entire area is imaged in the IR spectrum - but the resolution is typically 100m/pixel - and thus isnt much use.  Victoria is easily visible as a quite bright - sharp crater in this image - http://themis-data.asu.edu/img/browse/i … 415019.png  - approx half way down  - just left of centre - in a slightly darker area.

At 18m/pixel for the Visible imagery - I doubt that it could resolved dunes as we know them - they'd have to be on the order of 30 odd metres across to be resolved above 'noise'

There's also MOC imagery to look at (afterall - for every Themis VIS image pixel - MOC will have 144 - and up to 400ish using CPROTO)  - the easiest way is via the MarsOWeb interface at http://marsoweb.nas.nasa.gov/landingsit … 2003/mocs/ -

Skip the crappy java map and go straight to - http://marsoweb.nas.nasa.gov/landingsit … ion08.html  if you want Meridiani
As you can see however - Victoria hasnt been caught on any publicly available MOC imagery yet.

I verified this using the Malin Space Science interface ( they built and 'drive' MOC ) http://www.msss.com/moc_gallery/]http:/ … c_gallery/

For each release 'batch' - you want  section 19 ( http://www.msss.com/moc_gallery/e19_r02 … /mc19.html for example )

You can see the Opportunity ellipse is well imaged up the top right there (2deg S, 5 Deg W ) and similarly is quite well imaged in a few other image releases. However - Victoria hasnt been 'got' yet ( it's outside the landing elipse for goodness sake!! ) -but I'm fairly confident that since Sept. '03 - it WILL have been imaged and we can expect the MOC images from Sept '03-> Feb '04 to be released early October (I think) - and when that happens - It'll be full of ROTO targetted images of both landing sites ( and Beagle 2 as well ) - at which point I'll try and augment my map - and even go up to 1m/pixel with some of the CPROTO imagery

Doug

I've put together a 2m/pixel map using THEMIS and some MOC imagery of the area where Opp is now - down to Victoria. 

It's 5700 metres from the southern rim of Endurance to the Northern rim of Victoria.

To give a sense of scale - from Eagle Crater to the point they entered Endurance - is 700 Metres.

I've reduced the map down to 4m/pixel ( still 4x great than the Themis res )

They're going for victoria crater - thats a HUGE 700m+ crater some miles away - THAT - will be a panorama worth waiting for

Doug

We dont need to go and look at the heatshield to see dust deposition

Infact - thats a bad place to look at it - it probably got caked in it on impact

You want to study atmospheric dust deposition - you study solar array output - and the sun dial.

Infact - just look at these

Sol 2

Sol 200

See how different they look - thats just dust deposition, and it's a LOT worse with Spirit.

But - there's plenty of reasons to visit the heatshield...

- Engineering - see how it stands up to entry and impact
- Science - it's dug a BLOODY GREAT HOLE Far bigger than the wheels could trench
- Cool Factor - just as cool as the empty nest images imho.

Well - I googled until I could find WHEN the image of the dust devil was taken -

http://www.aas.org/publications/baas/v3 … 98/359.htm  told me it was Sol 11 whilst taking the gallery pan.

SO - off to the PDS where I know every Pathfinder image is online

http://pds.jpl.nasa.gov/]http://pds.jpl.nasa.gov/

Into the Imaging section - into resources and into the Pathfinder section

http://pds-imaging.jpl.nasa.gov/Admin/r … s_mpf.html

MPFL-M-IMP-2-EDR-V1.0 is what I want - and Sol 11 would be in the first section of these three - http://pdsimg.jpl.nasa.gov/data/mpfl-m- … -edr-v1.0/

Browse - with Mars as the target and you get a list of all imaging sequences

http://pdsimg.jpl.nasa.gov/data/mpfl-m- … ...dex.htm

As you can see - there's several tiers and channels of Galllery Pan. Obviously with so much sky in the view - it would be tier 5 (top tier) - so I opened up all three channels pages - and found the image that matched the profile of the published scarey-colours image

http://pdsimg.jpl.nasa.gov/data/mpfl-m- … ...033.htm

(14th image along)

And there we go.

Easy if you know what sequence it was taken in ( gallery pan ) and where to look

Doug

I would not be at all suprised to see MSL targetted to Meridiani.

Doug

I've heard of extensions that would run into the next decade as part of super-extended missions

Doug