# Your thoughts on this picture from Mars? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [January 20, 2005, 5:16pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745 "2005-01-20T17:16:46Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [January 20, 2005, 5:16pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/1 "2005-01-20T17:16:46Z")
Other worlds are in the news at the moment - but leave Titan alone for a moment, and look at this from Mars: [![](https://mars.nasa.gov/mer/gallery/all/1/p/058/1P133331837ESF0800P2556R1M1.JPG) ](https://mars.nasa.gov/mer/gallery/all/1/p/058/1P133331837ESF0800P2556R1M1.JPG) The resolution is not brilliant, I know, but what is that in the middle? To an Earth-biased observer, it looks like a puddle of water in a shallow depression in some sand, reflecting a cloudy sky. I imagine that’s not too likely on Mars, but what is it likely to be? I suppose it could be an anomalous area of _very_ fine grains of sand, but why just here at the bottom of a hollow? Any thoughts? Unfortunately I don’t have any more info on the scale, location etc; I just came across it on Usenet. ---
**Author:** ![Lord\_Ashtar](https://avatars.discourse-cdn.com/v4/letter/l/7ea924/32.png) [@Lord\_Ashtar](https://boards.straightdope.com/u/Lord_Ashtar)\ **Post date:** [January 20, 2005, 5:18pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/2 "2005-01-20T17:18:35Z")
I’d be curious to know where on Mars this was taken. I’m pretty sure they’ve found water ice near the poles, so if this is near there it very well could be a small puddle (assuming they took this near the middle of the day when it would be warm enough to melt into liquid). ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 20, 2005, 5:34pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/3 "2005-01-20T17:34:37Z")
Doesn’t look like a puddle of water to me at all. If it were water, I’d expect the gravel or sand at the edge to be darker, since some some water would be drawn up by capillary action. Look at similar puddles here on Earth. To me it looks more like a section of rock exposed by wind. ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [January 20, 2005, 5:40pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/4 "2005-01-20T17:40:19Z")
> [@Q.E.D.](#): > > Doesn’t look like a puddle of water to me at all. If it were water, I’d expect the gravel or sand at the edge to be darker, since some some water would be drawn up by capillary action. Look at similar puddles here on Earth. To me it looks more like a section of rock exposed by wind. What if all the sand _is_ wet, and therefore dark, except for the high points, the wind-whipped ridges, which appear light? (Just playing devil’s advocate here - I’m not saying that is what we’re looking at) ---
**Author:** ![ShibbOleth](https://avatars.discourse-cdn.com/v4/letter/s/848f3c/32.png) [@ShibbOleth](https://boards.straightdope.com/u/ShibbOleth)\ **Post date:** [January 20, 2005, 5:44pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/5 "2005-01-20T17:44:35Z")
Looks kind of like a footprint to me. ---
**Author:** ![Casey1505](https://avatars.discourse-cdn.com/v4/letter/c/dc4da7/32.png) [@Casey1505](https://boards.straightdope.com/u/Casey1505)\ **Post date:** [January 20, 2005, 5:48pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/6 "2005-01-20T17:48:08Z")
Just looks like a smear on the lens. ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [January 20, 2005, 5:52pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/7 "2005-01-20T17:52:41Z")
I’ve found a colour version of the pic - but again, I have no other details. Is it true colour? No idea. ☹ [http://mars.gh.wh.uni-dortmund.de/mer/opportunity/058/1P133331559ESF0800P2556L5M1\_L4L5L5L5L6.jpg](http://mars.gh.wh.uni-dortmund.de/mer/opportunity/058/1P133331559ESF0800P2556L5M1_L4L5L5L5L6.jpg) It certainly looks like a real “thing” anyway, not a smear on the lens. Looks a bit more rock-like here though. The JPEG artifacts don’t help any… ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [January 20, 2005, 6:04pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/8 "2005-01-20T18:04:57Z")
Looks like ice or exposed rock. Until someone drills into it we wont know. ---
**Author:** ![Casey1505](https://avatars.discourse-cdn.com/v4/letter/c/dc4da7/32.png) [@Casey1505](https://boards.straightdope.com/u/Casey1505)\ **Post date:** [January 20, 2005, 6:12pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/9 "2005-01-20T18:12:34Z")
Looks even more blurry, IMO, in color than it did in black and white, like it was seen through a wind blown drop of water (or hydraulic fluid, oil, or some other semi-clear liquid). Neat pic, either way, I just don’t see what you all are seeing. ---
**Author:** ![RickJay](https://avatars.discourse-cdn.com/v4/letter/r/bb73d2/32.png) [@RickJay](https://boards.straightdope.com/u/RickJay)\ **Post date:** [January 20, 2005, 6:24pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/10 "2005-01-20T18:24:18Z")
It sure looks like a smear to me, or some flaw on the film. Actually, it kind of looks Photoshopped. It doesn’t look like an object at the same distance as the background at all. ---
**Author:** ![Podkayne](https://avatars.discourse-cdn.com/v4/letter/p/edb3f5/32.png) [@Podkayne](https://boards.straightdope.com/u/Podkayne)\ **Post date:** [January 20, 2005, 6:28pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/11 "2005-01-20T18:28:32Z")
I’d want to know the image scale and the context and see the original FITS image before answering, but, tentatively I’d say it’s the nearly flat rock (or the flat top of a rock) that’s buried almost entirely by soil. I doubt we’re looking at water in any from. The relief looks all wrong for a puddle, liquid water wouldn’t be stable, and there’s just not that much ice laying around at that latitude. I have some friends who work on the rovers; I’ll see if I can catch them this afternoon and get an opinion. ---
**Author:** ![Podkayne](https://avatars.discourse-cdn.com/v4/letter/p/edb3f5/32.png) [@Podkayne](https://boards.straightdope.com/u/Podkayne)\ **Post date:** [January 20, 2005, 7:21pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/12 "2005-01-20T19:21:22Z")
Here’s what the [file number](http://marsrovers.jpl.nasa.gov/gallery/edr_filename_key.html) means: 1P133331837ESF0800P2556R1M1 1: Opportinuty P: Pancam 133331837: Spacecraft clock number (Seconds since Jan 1, 2000) ESF: Product type: Sub-frame, raw with no camera model linearization or radiometric correction. 08: Taken at the 9th Opportunity Site 00: Taken during the 1st drive at the 9th site. P2556: Command sequence (Pancam sequence) R: Taken by the right camera eye of Pancam. 1: 436 nm shortpass filter (blue) M: Prodiced by MIPL (OPGS) at JPL 1: Version 1 Ha HA! [Found it!!!](http://marsrovers.jpl.nasa.gov/gallery/all/1/p/058/1P133331837ESF0800P2556R1M1.HTML) And here are the other [Sol 58 Opportunity Pancam images](http://marsrovers.jpl.nasa.gov/gallery/all/opportunity_p058.html) They probably made that false-color image by combining images from different filters. Here are some [better false-color images.](http://www.lyle.org/mars/synth/1-058.html) Sol 58 was just after Opportunity left Eagle Crater. Here’s a cool [Look back from the front Hazcam](http://marsrovers.jpl.nasa.gov/gallery/all/1/f/058/1F133332850EFF0824P1201L0M1.HTML). Nothing specific about this image in the [updates](http://marsrovers.jpl.nasa.gov/mission/status_opportunityAll.html#sol58). Looking at the other images, it looks like there’s a depression where some of the soil has been removed (maybe by wind). To me, especially looking at the other filters, it looks like a flat rock that’s just barely revealed. ---
**Author:** ![Podkayne](https://avatars.discourse-cdn.com/v4/letter/p/edb3f5/32.png) [@Podkayne](https://boards.straightdope.com/u/Podkayne)\ **Post date:** [January 20, 2005, 7:26pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/13 "2005-01-20T19:26:14Z")
[More near-rocks for comparison from Sol 57](http://marsrovers.jpl.nasa.gov/gallery/all/opportunity_p057.html). Be sure to click all the way through to the highest res images for the best view. ---
**Author:** ![Podkayne](https://avatars.discourse-cdn.com/v4/letter/p/edb3f5/32.png) [@Podkayne](https://boards.straightdope.com/u/Podkayne)\ **Post date:** [January 20, 2005, 7:27pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/14 "2005-01-20T19:27:27Z")
Bleh. “Near-buried rocks,” I mean. ---
**Author:** ![The\_Chao\_Goes\_Mu](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/the_chao_goes_mu/32/3191_2.png) [@The\_Chao\_Goes\_Mu](https://boards.straightdope.com/u/The_Chao_Goes_Mu)\ **Post date:** [January 20, 2005, 7:30pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/15 "2005-01-20T19:30:46Z")
It’s that damned one -egged BigFoot again. ---
**Author:** ![Cervaise](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cervaise/32/16693_2.png) [@Cervaise](https://boards.straightdope.com/u/Cervaise)\ **Post date:** [January 20, 2005, 7:46pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/16 "2005-01-20T19:46:14Z")
Looks like someone hocked a loogie. ---
**Author:** ![The\_Chao\_Goes\_Mu](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/the_chao_goes_mu/32/3191_2.png) [@The\_Chao\_Goes\_Mu](https://boards.straightdope.com/u/The_Chao_Goes_Mu)\ **Post date:** [January 20, 2005, 7:47pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/17 "2005-01-20T19:47:43Z")
> [@The Chao Goes Mu](#): > > It’s that damned one -egged BigFoot again. Dammit! :smack: When will I ever learn to “preview?” Um, that should’ve read “one-legged” ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [January 20, 2005, 8:52pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/18 "2005-01-20T20:52:30Z")
Thanks, **Podkayne** , for digging up (heh) some solid (heh heh) info. Looks like it’s just a rock. Nothing to see, here. What have y’all got to say about [this one](http://www.hal-pc.org/~jsb/ColorMars.jpg), though? 😃 ---
**Author:** ![Cervaise](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cervaise/32/16693_2.png) [@Cervaise](https://boards.straightdope.com/u/Cervaise)\ **Post date:** [January 20, 2005, 8:58pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/19 "2005-01-20T20:58:10Z")
That’s interesting, but I need more info. Come on, somebody throw me a bone, okay? 🙂 ---
**Author:** ![Podkayne](https://avatars.discourse-cdn.com/v4/letter/p/edb3f5/32.png) [@Podkayne](https://boards.straightdope.com/u/Podkayne)\ **Post date:** [January 20, 2005, 9:07pm UTC](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745/20 "2005-01-20T21:07:16Z")
Oops, looks like my rock hypothesis was wrong. My friend pulled up the real images in all the different filters, made 3-D images, the whole nine yards, and examined them carefully. In his learned opinion, it’s a relatively fresh deposit of sand or dust at the bottom of a depression. Compare the red and blue images. In the red, the deposit is brighter than the surrounding soil, and in the blue it’s darker; that indicates that it’s redder than the soil around it, which is more characteristic of sand or dust than rock. The actual images look a lot less weird than the JPEGs, which do funny things with the contrast in texture between the clumpy soil and the smooth deposit. My friend thinks it’s a pretty cool picture, and thanks you for giving him a reason to goof around with something that is not his thesis for an hour, as do I. Also, I’m feeling rather nauseated from the 3D glasses, so I think I’m going to rest my head on the desk for a while. _woozy_ 🙂 [Next page](https://boards.straightdope.com/t/your-thoughts-on-this-picture-from-mars/285745.md?page=2)