Rock Formation That Looks Like "Alien Doorway" Spotted on Mars

NASA currently has a few missions going at Mars, and one of them recently captured a photo that has set the internet abuzz. Earlier this month, the Curiosity rover relayed an image of a rock formation that appears to have a chunk cut out of it, almost as if it is the doorway to something buried under the Martian surface.

Despite its smooth edges and hallway-like features, scientists believe it to be a natural rock formation. "It's just the space between two fractures in a rock,"Mars Science Laboratory scientists Ashwin Vasavada recently told Gizmodo. "The fractures we see in this area are generally vertical," he explained. This particular doorway-shaped fracture likely formed in one of two ways."

He added, "I think what we have here [is] either two vertical fractures, where the middle piece has been removed, or one vertical fracture, and the blocks have moved apart a little bit."

Curiosity has been on the Martian surface as a part of a NASA mission since August 2012. It was designed to explored the planet's Gale crater, a sizable hole on the planet's surface some 96 miles across. To date, no concrete evidence has been discovered supporting the theory life once existed on the planet.

"Curiosity explores Gale Crater and acquires rock, soil, and air samples for onboard analysis," NASA says of the mission. "The car-size rover is about as tall as a basketball player and uses a 7 foot-long arm to place tools close to rocks selected for study. Curiosity's large size allows it to carry an advanced kit of 10 science instruments. It has tools including 17 cameras, a laser to vaporize and study small pinpoint spots of rocks at a distance, and a drill to collect powdered rock samples. It hunts for special rocks that formed in water and/or have signs of organics."

More about the Curiosity mission, and others on Mars, can be found on the NASA website here.