[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.