Images sent from Mars by the Curiosity rover show a kind of door carved into a rock. A clue to the existence of aliens? Geologists have a completely natural explanation for the phenomenon.

The Curiosity rover has been on the move on Mars for almost ten years. In 2012 it was dropped there by NASA as part of a program to explore the planet and has been sending images and data to Earth ever since. This gives mankind an impression of what it looks like on the red planet – and some images cause confusion.

One of the rover’s most recent photos shows a rock formation containing what appears to be a door leading to a passageway. Wild speculation immediately followed: How did this entrance come about? Some even interpreted the image as an indication that there is intelligent life on Mars. In the meantime, experts have dealt with the topic in more detail. They rule out that the door could have been created by extraterrestrials.

Entrance on Mars created by erosion

“It’s a very strange picture,” British geologist Neil Hodgson told Life Science. “But to make it short: It looks like natural erosion to me.” With the help of other pictures that show the immediate vicinity of the site, he was able to see that the rock layers, called strata, slope down on the left side and are higher on the right side.

The layers were deposited “perhaps four billion years ago in sedimentary conditions, possibly in a river or a windblown dune,” according to Hodgson. Martian winds then blew away the layers, causing vertical fractures in the rock to occur naturally, for example through weathering of the rock. These can also be seen in the pictures that Curiosity sent.

“Normal Geological Processes”

This is how the mysterious “door” was ultimately created: a large boulder fell out through the collision of the vertical fractures with the rock layers. “Gravity isn’t that strong on Mars, but it’s strong enough to bring about such an event,” Hodgson said.

Other scientists are also certain that the opening has nothing to do with Martians. “There is nothing strange about this picture at all,” Sanjeev Gupta, professor of geosciences at Imperial College London, told the Daily Telegraph. “These are just normal geological processes.”

Sources: Nasa / Telegraph / Science Life