Planet Four Talk

What are these? Does mars have acne? Or could they be flocks of martian sheep? :P

  • sambroster by sambroster

    white spots?

    Posted

  • bleasdales by bleasdales

    boulders ?

    Posted

  • jb1995 by jb1995

    They look like boulders, but surely boulders would leave a shadow

    Posted

  • wassock by wassock moderator

    Hi there. Boulders do leave a shadow BUT.
    In most of the images you will see here the sun is shining from somewhere to the bottom right of the image (the whole thing is upside down with north at the bottom. This makes you interpret raised features as depressions and pits as lumps. So the first thing to do when trying to figure out where things are is to figure out where the sun is and what that means for the bright and dark bits in the images.
    Thus what looks like boulders in this pic have shadows on the bottom right, facing the sun, so that bit is sloping down away from the sun and the other side where it slopes up again catches the sun and looks much brighter, probably enhanced by the presence of ice in the hole. If you look more or less dead centre of the image there are two horizontal features which have the shadow on the top side. So here we are looking at raised lumps with the sun shining on the bottom side with the top in shadow.
    I did manage to spend a couple of hours the other night were I magically started seeing things the right way round, but most of the time I see channels as hills, particularly wrt the spiders which are carved out features not the system of ridges that they look like.

    Posted

  • AUricle by AUricle

    jb,

    A combination of things in respect to viewing these images, conspire to trick the human eye.I could explain this cruel trick, but it's already been done on the P4 blog site. Read it before you go any further to save yourself A LOT of frustration. 😉

    http://blog.planetfour.org/2013/01/16/if-it-looks-like-a-ridge-its-a-valley-1st-rule-of-mars/ Happily for us,the rule is not a factor in classifying the images. The things we are looking for look the same, regardless of the orientation of the image. It is the surrounding terrain that 'changes'. Many times, dramatically!

    Posted

  • wassock by wassock moderator

    AUricle, thanks I was just coming back to post that link.

    jb, if you'd like a look at the image in a wider context have a look at the large image in this thread http://talk.planetfour.org/#/boards/BPF0000002/discussions/DPF0000ccj
    I think your image comes from somewhere near the bottom

    Posted

  • AUricle by AUricle in response to wassock's comment.

    wassock,

    I wouldn't have even posted if I had seen that you already did. When I started the post, there were no responses, but I took my time with it, actually going over to the blog site (have you seen the new article from Dr Candice Hansen(?) Principal Investigator for the P4 project.) Some good stuff!.......anyway, I read that then came back to finish my response. So you obviously finished yours 20 min or so ahead of me. Well, I'd say 'jb' got his money's-worth on this one 😉

    Posted

  • JellyMonster by JellyMonster

    I had to spruce this image up a bit as it looked too much like the magnolia painted walls in my flat 😃. The usual edits have been enforced to allow users to see it in a better light (should work for most).

    ![Divots] (https://dl.dropbox.com/s/9175sqa9hr2z9ms/R-50e740ff5e2ed21240003054.jpg)

    Posted

  • jb1995 by jb1995

    Thanks folks, explains a lot.

    Posted

  • Kitharode by Kitharode moderator

    I think wassock has it right when he says there will be some enhancement of the light in the 'pits' due to presense of ice. I don't think there's any denying that the small spider channels are intimately linked to these objects in some way.

    I've not seen anybody take these on as a 'proper project' yet (might be wrong there). We've kicked a few boulders around, which nearly turned into 'stalagmite' thingys, but not seen anybody collecting pit/spider relationships. It'd be good to know what we know about that, even if it's only "we know nothing" or even "there's nowt to know". 😉

    Posted