The latest thing found on Mars that looks a bit like something else has caused consternation on conspiracy blogs.
This time the weird object looks like an alien skull, but isn't, obviously.
The rock was discovered by the $2.5 billion Curiosity rover, currently trundling about on the Red Planet's surface.
And it is pretty interesting, if you're trying to make it look like a skull in your mind, even though you know that it's not a skull.
It appears to have defined teeth and a jaw. Some bloggers even claim it has a "metal blade or arrow embedded in the jaw bone".
Well, it does when you edit the picture to look like this:
... Which is the sort of thing these people do.
Alas, Nasa has decided not to investigate, having as it does plenty of actual science to do on the surface of Mars which does not involve examining every frog shaped, artillery-shaped or ball-shaped rock that turns up within 100 feet of the robot.