6 November 2009
Mars Art: Mind-blowing Swiss Cheese
Posted by Ryan Anderson
First of all, a reminder to go vote on my article about MSL, which is a finalist in the scientificblogging.com science writing competition.
Ok, done? Good. I wanted you to do that before I showed you this image because it may very well break your brain. This is a HiRISE image of the so-called “swiss cheese” terrain at the south pole of mars. The terrain is formed by the sublimation of CO2 ice, which forms weird rounded pits. Yes, the round things in this picture are pits.The smooth parts are mesas and the illumination is from the lower right. Pictures like this always make my brain hurt because for some reason I want to see the round depressions as bulges! And if you think this is bad, try watching a scientific presentation with dozens of pictures like this, with varying orientations and illumination angles. I rarely get anything out of Mars south pole talks because my brain is so busy struggling to see the images properly.

Believe it or not, illumination is from the lower right in this image. Click the image to go to the HiRISE page and check out the full sized versions.
See my rotated picture at: http://twitpic.com/oi7vc
Yeah, playing with the orientation sometimes helps, but in this case, even with your rotated version they keep popping in and out for me.
I find it helps most to focus on the flat mesa tops and not the round parts.
Thank you for mentioning this.
I have this problem all the time, particularly with Mars images for some reason.
What annoys me, though, is that it’s so rarely acknowledged: all that’s needed is to say which direction the light is shining from. Then, at least if you can’t flip the image you can understand what’s being discussed.
Some papers do specify lighting direction, particularly if it is ambiguous. But you’re right, it’s not that hard to add that bit of info and it can really help!
this is weird but anything discovered in science is weird as there are many weird and wonderful things sill to be found in science
Joh Christopher Sunol
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