NASA’s Curiosity rover has photographed a bizarre, coral-shaped rock on Mars, believed to have formed billions of years ago.

The surface of Mars looks like an empty red wasteland. But if you look a bit closer, the remnants of an ancient alien civilization begin to take shape. At least, that's the conclusion of George J.

"The structures that we were able to identify in the images are clearly the mouth of a river into an ocean." The post ...