
Enthusiasts lit up social media recently with images of what appeared to be a “doorway” into a hillside on Mars. Was it, some wondered, evidence that the Red Planet could be, or have been, inhabited by aliens?

Enthusiasts lit up social media recently with images of what appeared to be a “doorway” into a hillside on Mars. Was it, some wondered, evidence that the Red Planet could be, or have been, inhabited by aliens?