The circular surface feature was photographed by the Mars Reconnaissance Orbiter in the in Athabasca Valles, north-central Elysium Planitia. It’s hard to miss because it’s in the middle of a smooth area, making it look like an island (although “cookie” sounds a lot more interesting).
NASA calls it a mound and suggests that it was created when lava pushed something up from beneath at some point in time. The organization also states that it seems like material is missing from the mound, possibly ice that melted as the lava approached. The Athabasca region has more of these enigmatic formations. What could they be?
Let’s start with the almost perfectly round shape of this formation. Was this a volcano crater? Volcanoes are one of the few natural phenomena that create these shapes, and there are many of them on Mars. If it was a crater, then it must have cooled down so suddenly that we can still see the bubbling lava, frozen in time. Otherwise, there must be something underneath the mound that shaped the lava flowing over it.
it could be some older rock formation, pushed up by later volcanic activity. But what if it is something completely different? Could the remains of a Mars settlement be hidden in the mound? What if there actually was life on Mars in ancient times, and this is how they lived? The rounded, artery-like shapes were made by lava flows. They could easily cover up angular shapes of buildings, canals and yards.
If ancient Martians were human-like, this could be the case. But if it is actually an alien settlement, then our imagination is the limit. Sci-fi movies give us examples of yet imaginary construction techniques and shapes. Living-quarters could be organically grown, blended in with the environment. There could be power-supply structures that we can’t even begin to understand.
Unfortunately, we would need a much bigger Mars rover to excavate and find out more about the Mars cookie.