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Mars landing

The mission is already producing stunning images.

http://marsrovers.jpl.nasa.gov/newsroom/pressreleases/20040104a.html

-- Jeffrey Berg (email)


.

Interesting piece of software released by NASA to coincide with Spirit's landing.

"NASA has released Maestro, a public version of the primary software tool used by scientists to operate the Mars Exploration Rovers from the Jet Propulsion Laboratory. Anyone can download Maestro for free from http://mars.telascience.org and use it to follow along with the rovers' progress during the mission. You can use Maestro to view pictures from Mars in 2D and 3D and create simplified rover activity plans. During the mission, updates will be released for Maestro containing the latest images from Mars." Mac users will need to install the Java3D update available at http://docs.info.apple.com/article.html?artnum=120289#English.

-- Ben Stewart (email)


Moving panorama at

http://www.spaceref.com/news/viewsr.html?pid=11443

-- Edward Tufte


I was too impatient to wait for NASA to release a true-color panorama, so I updated an earlier composite photograph to match the single color photo they released today: http://www.style.org/ marspanorama/.

-- Jonathan Corum (email)


Yes, NASA originally posted an 8MB JPG of the color photo, which they describe as the highest resolution image ever taken on the surface of another planet. They have also added a smaller 3.5MB TIFF.(may require reloading or refreshing the screen)

[link updated March 2005]

-- Jonathan Corum (email)


Note mix of eroded, smoothed rocks and sharp-edged fragmented rocks. Imagine a million-year time-lapse image.

-- Edward Tufte


NASA's collection of annotated image details describes the dark brown "footprint" marks at lower right as disturbed soil left behind by the deflation and retraction of Spirit's airbags.

-- Jonathan Corum (email)


There has been a recent focus about the wind affects polishing the rocks. But something in the picture keeps bugging me.

I could be out on a limb here, but not only does the wind seem to polish the rocks, but some wind eddying might have shaped some patterns into local topology rather than creating ripples. By ripples I mean like a tide combs a beach or large wind currents combs the desert to create thousands of parallel zig zags.

I made a quick highlight to show some spiraling affects that could be present here.

Powerful eddying might also be why there are random areas of less debris density than others which were not created by the lander's cushions. I am a weather amature and hardly know the consistancy of Martian soil or the affect of dust particals on the environemnt so please remember a grain of salt.

Seems far more likely a proposition than a boot print?

I can't seem to find any data sources such as wind speeds, direction or otherwise from the lander. I'd be interested to see it.

-- Jeffrey Berg (email)


Although the chances are, effectively, infinitely more likely than a "footprint", this may, or may not be, a result of the same process that shows that "feature".

The patterns you describe seem to be marked by relatively large rocks - though I've not yet seen anything that helps to scale anything in the picture (hence, the "footprint" could be about five centimetres long), they are considerably larger than the sand they are buried in. In order for the wind to move these it would have to be very fast, especially in a rarified atmosphere (with less "air" to provide the mass).

I wonder if the patterns you see are to do with the eye being drawn along lines created by the shadows so the brain "sees" some order within what is, actually, more random. Would the spirals change if the light was from a different angle? This should be relatively simple to test as there must be a picture taken of the same area at a different time of day. It would, again, be more obvious if the area was filmed from a different angle.

There are ground-based processes that can affect the stone patterns on, and within, the ground. For example frost-heave can move stones into circles or hexagons, with clear spaces in between (I am not saying that's what's caused the clear patches here). Of course frost-heave requires water (or a freezing liquid), and is, I think, one thing that the Mars explorers are looking for evidence of, to try and find evidence of water on the planet.

My geographical and meteorological knowledge have been a bit unused since I left the Met. Office seven-odd years ago, so I'd recommend a few grains of salt with my answer, too.

-- Adam (email)


Haven't read the link, but re-Beagle 2: The US orbiter was the first one to try and pick-up a signal several days ago, but the two hadn't been tested together, so when it turned up blank, there was still some hope. The European orbiter, Mars Express, was in position yesterday, and was the best hope to pick up a signal. It also turned up a blank. There are some more chances, the next being tomorrow, but one of the scientists on the team now rates the chances as being about 5% for contact to be made.

However, my reading was that the main mission was Mars Express and Beagle-2 was added as a bonus after-thought (though an $80-100 million afterthought), so despite the lander failure, it's not a total write-off. Mars Express's main mission is to look for water and one of it's instruments may be able to pick up traces of ammonia in the atmosphere from the Beagle-2's air-bags, which would be quite impressive.

The US orbiter has taken pictures, apparently, too.

Some details here.

-- Adam (email)


Very helpful account from today's science section in the New York Times: http://www.nytimes.com/2004/01/08/science/08MARS.html?ex=1388898000&en=417576d277bc8faf&ei=5007&partner=USERLAND

[link updated March 2005]

-- Edward Tufte


This interactive map of Mars has some interesting features, if you want to explore the sites yourself, from above.

Map

-- Adam (email)


As regards the mysteries of the "mud", the disturbances suggest that the surface material is lighter in colour than the lower material. This could be to do with a crust formed as in the above article, but could it be to do with a "bleaching" effect by the sun over a long period? Or maybe if there was a liquid flowing over and into this area, some leaching took place, and the surface material has been little disturbed since? As the wind can throw up a lot of dust it does suggest that the surface could be "crusty" to prevent too much mixing?

Compare the disturbances to photographs of the moon landings and you see that the material does behave in a similar way in places. Dry dust, keeping what look like vertical faces, etc. Could the grains be of a similar form? Is there an optical property of the material that makes it look darker? In the same way the lunar dust reflects light in particular ways?

It would also be interesting to see the grain size. I wonder if you could get similar effects by punching into a bucket of dark flour? I get the impression that smaller grains can "meld" together and keep structure better under pressure than larger grains, even when dry. Unfortunately researching the assumptions that these ideas are based on would take more time than I have, but fortunately there are people at JPL paid to do it for us. I'd be interested to hear the opinions of any geologists/geographers out there.

-- Adam (email)


That's an interesting theory. As far as I know there are no seismometers on the rovers, but there was one on Viking 1 and I think that there will be one on the 2007 mission(s).

If you look at the link below, you'll see weekly weather forecasts for the landing sites, plus some interesting links to pages with images of dark streaks created by "dust devils" that whip up the brighter, orange surface dust to expose darker, lower dust below it.

http://www.msss.com/mer_mission/index.html

Looking at the pictues from July and December last year, whatever re-coates the surface dust (quakes, lighter winds?), or makes the darker dust lighter (bleaching) does a very good job in five months. Seeing as all of this was known from images, and there have been landers doing a decent job for years, there is probably some well advanced theories as to the process involved, somewhere?

As for your theory of eddies moving the rocks, well the global storms may achieve velocities to move some. I think we'd need to see the velocities and atmospheric densities to know for sure.

http://www.spacetoday.org/SolSys/Mars/MarsThePlanet/MarsDustStorms.html

I think I've been in handful of salt territory for some time, now.

-- Adam (email)


Thanks for the weather link.

The soil issue I suppose will just take time to hear about from NASA.

On another note, I wonder if the moons are visible at night? Do they have seperate Phases? Does one ever appear to pass in front of another creating a local quasi eclipse? It would be fascinating to get a shot of both in one skyline.

-- Jeffrey Berg (email)


Will keep an eye out for moon data.

However, NASA are very interested in the area around the "footprint" and are planning to send Spirit to it to have a look. This 3-D model made from the images suggests that the "footprint" is about 5cm long. It's just to the right of the "triangular" shaped rock in the top left of the image - looking like the person was walking away from the viewer.

Also, this more overhead image shows that it actually isn't quite the right shape, and it's the flatter view of it that makes it look more like a footprint.

Anyway, the "rolled up" piece of soil looks interesting.

-- Adam (email)


I don't have a link at the moment, but Spirit has taken a picture of the Martian soil at very close-up which shows it to have "cocoa"-like clumping properties (NASA's choice of words).

Incidentally, the European Mars Express has returned its first image of the surface of Mars, the resolution is 12m per pixel. The image looks like a painting or computer game graphics, but that's not particularly surprising at that resolution, given the nature of the landscape. Also noticeable is the fact that the image was taken with a "Stereo" camera.

http://www.esa.int/export/SPECIALS/Mars_Express/index.html

It is intended to map the entire surface at 10m per pixel, with selected areas at 2m per pixel. More details can be found at the above website, especially under the "About Mars Express" section.

-- Adam (email)


Meanwhile, a new map of Phobos suggests a new explanation for the mysterious crater chains that used to be thought of as emanating from Crater Stickney:

http://www.planetary.org/blog/article/00001391/

A global projection makes it pretty clear that the common feature of the chains is their orientation with respect to Phobos' motion in Mars orbit. The obvious conclusion is that the chains are due to ejecta streams from the Martian surface itself, like when you drive into the spray from the car ahead washing its windscreen.

-- Derek Cotter (email)




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