[RaecKK]

For anyone not familiar, this photo was snapped by the NASA Mars rover Curiosity: http://mars.jpl.nasa.gov/msl-raw-images/msss/00184/mcam/0184...

Zoom in all the way, scroll up and to the right as far as possible, then scroll down just a tiny bit and look at the rock. That rock has a face on it? Definitely a WTF from me.

I am so tired of seeing visual evidence dismissed by people who refuse to even consider it if it's not endorsed by some large "respectable" institution. You mean to say this rock is just a naturally occuring anomaly? Really?

[huxley]

In the late 1890s, a group of gentlemen-researchers named Henri Duveyrier, Victor Largeau, Erwin von Bary and H. S. Cowper found something incredible, what appeared to be a megalithic structure in Tripoli.

Upon further investigations they found large numbers of them throughout northern Africa, they described all kinds of megalithic structures: dolmens, menhirs, cairns, cup stones, and sacrificial altars.

Speculation was that this was a previously undiscovered Neolithic civilization, in describing the Senams, Cowper wrote "there had been originally no less than eighteen or twenty megalithic trilithons, in a line, each with its massive altar placed before it." Amazingly each altar had an obvious drain trench where blood from the sacrifices flowed. Cowper even speculated at one point that the builders of these cyclopean structures were involved in the raising of Stonehenge.

They were all well-respected, H.S. Cowper had done some early significant work identifying and describing megalithic structures in the UK, so obviously he knew what he was talking about.

A book with the findings was published to great anticipation. Unfortunately as the book was going to press, an article was written by J. L. Myers, Arthur Evans, and W. Gowland who actually knew what those structures were.

They were Roman-era oil presses.

For a brief period of time, Cowper denied this was possible pointing to Berbers that referred to the structures as idols, but for anyone who knew anything about Roman oil presses, these were fairly commonplace.

That's the long way of saying that the human mind has a tendency to find patterns and to try to explain those patterns based on their expectations.

But sometimes a cyclopean altar is just an oil press.

[mikeash]

Pareidolia is a thing. And the Face on Mars is the top example on Wikipedia!

http://en.wikipedia.org/wiki/Pareidolia

Yes, that rock is almost certainly just a naturally occurring anomaly. People are built to find faces, even in things that aren't actually faces.

[kbenson]

Uhh, yeah? I don't see anything. I can't even find where I'm supposed to see a face. If it's that hard, perhaps what you are taking as obvious is simply because you've already identified it as a face so are subconsciously looking for it?

We've known for a long time that we are hardwired to recognize faces in sets of items that are definitely not faces, so why is it so hard to believe that you're falling prey to the same thing?

[RaecKK]

cropped with contrast added: http://postimg.org/image/n0nci70xp/

[mikeash]

It's a rather amazing coincidence that the "teeth" are the exact size and position of the JPEG macroblocks, wouldn't you say? The "eye" precisely occupies four macroblocks, too. Hmm.... I don't suppose you have an uncompressed original to compare to....

[kbenson]

And now I can see it, since it was explicitly pointed out. That doesn't make me think it's anything other than visual artifacts as you suggest, or a random bit of coloring.

[RaecKK]

I linked you to the original photo at NASA.gov, if you want to reproduce:

- Install Gimp

- Download the original Nasa image linked here: http://mars.jpl.nasa.gov/msl-raw-images/msss/00184/mcam/0184...

- Open the picture with Gimp. Crop out the face. Under the image tab, choose scale image. Scale the image to 300 percent of original size. There is an interpolation option when scaling the image. You have to choose Sinc Lancoz 3 because that is the interpolation option that will preserve the data in the jpeg pixels. If you choose cubic or linear it will be lost.

- Under the colors tab, open curves. NASA obscured this image by destroying it's dynamic content, so you will need to expand what is there by pulling the line to perfectly match the top and bottom of the image data. This will render the jpeg blocks and show you the image data they contain.

- Under the filters tab, mouse over enhance and choose the last option "Unsharp mask". Apply unsharp mask twice with the default settings. The picture will become clear enough to show.

[mikeash]

You linked me to a JPEG at NASA.gov. The features we're discussing line up perfectly with JPEG compression artifacts, suggesting they're not real. I was asking if you happened to have an uncompressed version of the image to compare to. I guarantee you that the JPEG file is not the original data that came off the rover.

[Jach]

I agree with all your comments in this thread (edit: and the one below, thanks for the great response :) ), though I have to wonder if you're really that confident in the idea that the features are merely JPEG compression artifacts, or if you're just asking for evidence that's hard to obtain. (Context for this line of thinking: http://lesswrong.com/lw/1ph/youre_entitled_to_arguments_but_...) You may have noticed the URL of the image is in a folder called "msl-raw-images", so even if they're JPEGs, as far as most people are concerned these are the 'raw' images. It's unclear to me how one would get rawer images without a Freedom of Information Request. Do you know a way?

Also, suppose he did come back with a rawer image that still showed the features. Is that going to convince you to say "oh wow maybe it was carved, it couldn't have naturally occurred!"? (http://lesswrong.com/lw/wj/is_that_your_true_rejection/)

[duskwuff]

By performing interpolation on the image, adjusting the color levels, and applying sharpening filters, you are seriously distorting the image. The resulting image is in no way representative of the original data.

[kbenson]

Okay, so that image looks to be on this page[1] as Mastcam: Right 2013-02-11 00:30:54 UTC. The full res link here is named slightly differently[2], but that appears to be the same landscape. It looks less whitewashed in these images, but around the same quality. There's another image with the same rock just before that time.

If you really want to go deep into this, try some of the other cameras around that time, maybe you'll see it from a different perspective.

1: http://mars.jpl.nasa.gov/msl/multimedia/raw/?s=184&camera=MA...

2: http://mars.jpl.nasa.gov/msl-raw-images/msss/00184/mcam/0184...

[TheOtherHobbes]

It's clear from this other shot there are no teeth there, and not much of a face either.

[scrollaway]

Nevermind jpeg compression, this is a simple example of pareidolia. Could be anything, really.

[mikeash]

I totally agree, but once I zoomed in on the original the macroblocks stood out like a sore thumb, and it was obvious that much of the "detail" revealed by the supposed zoom and enhance procedure was just macroblock borders.

[kjs3]

"Cropped with contrast added" == "imaged processed until I got to see something I wanted"

[jccooper]

And that's a face in a completely different way than I thought when I first looked at it in the original image. Sorry, it's just your (and my) natural pattern-matching misfiring. There's some accidental feature that looks like an eye, so the human brain wants to make the rest of it a face. But it's just a rock with a round feature on it.

[nilkn]

It's one of the larger rocks in the photo, to the right of the center. To me, it looks like the profile view of a fish's face.

[davidw]

Here's another version, enhanced and filtered a bit more:

http://bit.ly/192NjwG

[polemic]

If that's a WTF fror you, prepare to have your mind clean blown away.

https://twitter.com/facespics

[darkmighty]

It's interesting the objects people make absurd claims about are almost always faces. We have a large part of our brain dedicated basically to that task, so we're always seeking faces in the noise.

[mikeash]

Indeed. It's never a statue of a fish, or a turtle, or a bird. It's always a face.

[crusso]

"I am so tired of seeing visual evidence dismissed..."

We know that humans and many other animals recognize faces in a heavily biased way. It's the evolutionary reason why some butterflies and fish have eye markings. Their potential predators tend to see faces and may be intimidated by the implied size of the creature with those eyes or mistake the direction that the prey is headed.

Just from our own subjective experiences, we all see faces where we shouldn't: In clouds, in rock formations, in foliage, and even in burnt grilled cheese sandwiches:

http://www.nbcnews.com/id/6511148/ns/us_news-weird_news/t/vi...

As human beings who want to do Science, we have to recognize the limitations and biases of our own hardware or we're doomed to fail at evaluating reality.

[jkaunisv1]

Do you mean the rock about 40% down the image, at the bottom corner of a lighter colored diamond of terrain? Because all I see is an "eye" and maybe a mouth and none of it looks particularly sculpted/carved. I've seen more face-like images in the random shadows on my ceiling.

[super_mario]

Images taken later with better (higher resolution) equipment demonstrate the "face on Mars" is an optical illusion

http://en.wikipedia.org/wiki/Cydonia_(region_of_Mars)#.22Fac...

[tjradcliffe]

> I am so tired of seeing visual evidence dismissed by people who refuse to even consider it if it's not endorsed by some large "respectable" institution. You mean to say this rock is just a naturally occuring anomaly? Really?

Of course it is. That's by far the most likely conclusion.

Consider: Curiosity alone sends back between ten and 100 images every day that each contain thousands of objects (mostly rocks). So let's say there are 10,000 objects a day that people can look at (many more if you consider the tiny size of the "face" in this compressed image.)

I can't find any actual data on apophenia and pareidolia (finding patterns and faces in randomness, respectively) but given what we know about it the incidence is unlikely to be less than 0.1%, which means we'd expect to see ten objects per day in Curiosity images that look something like a face or other recognizable object, so if a fraction of one percent of those instances are fairly realistic we would expect to see something "very face like" a few times a year.

Those numbers are a bit hand-wavy, but they aren't out by orders of magnitude, and from them we can conclude that it would be pretty surprising if we didn't see something pretty facelike now and then in Curiosity imaging. If we didn't, it would be a major surprise. That we do... well, it's what we expect, so we dismiss it as evidence that what we see is of artificial origin. To do anything else would be to ignore what we know about human perception.

[mikeash]

It's interesting to consider the numbers from the opposite direction as well. If this stuff is real, where are all the non-face artifacts? If you plopped a rover down in, say, the ruins of Troy, you'd expect to have a bazillion photos of pottery and arrowheads and boring walls for every photo of a statue of a face. Why aren't the rovers finding anything like that? Humans have no mental bias for seeing such artifacts in random noise, so of course "we find faces, faces, and more faces, and nothing else" fits the pareidolia explanation much better than the actual-alien-artifacts explanation.

[libraryatnight]

Is this good visual evidence, though? I feel like if you want to get upset about this sort of thing you should find better examples. I appreciate your sentiment, but that image hardly seems like something about which to be excited.

That image looks like a rock and zooming in makes it look like a distorted rock. Coloring and manipulating the image is in my opinion getting farther from convincing there's something uncanny about that rock.

[mjgoins]

I've never so strongly wanted to simultaneously up-vote and down-vote a comment.

[lotsofmangos]

I see faces or figures in everything all of the time. I just now have looked at a 2 inch square of fairly coffee stained table and counted twenty of them. If I looked closer I could find as many as I wanted. String or hair tends to show me people in motion, blotchy surfaces are crammed with faces.

I saw a really good one the other day when I was looking unfocused at the floor and caught two patches of ground with either eye that resolved themselves really nicely into a stereoscopic image of a cartoon dog.

[jstalin]

Maybe you linked to the wrong photo, but I'm not seeing what you're referring to.

[RaecKK]

this: http://postimg.org/image/n0nci70xp/

[sp332]

Cropped version, and other imagery of the region https://en.wikipedia.org/wiki/Cydonia_%28region_of_Mars%29#....

[yiyus]

Yes, really.