The facehugger from the Alien series of movies was a fearsome creature, and now, NASA reports finding a structure on Mars that looks much like the terrifying being. However, researchers at the national space agency are certain the unusual object is a geological, rather than a biological, formation. 

The crab-like feature seen in the images is found in the mouth of a cave. The odd formation has excited some groups and individuals who contend the object is an alien life form. 

"It does appear alive. It may be a crab-like animal, or it also may be a plant. This object has many arms and one of them goes to the left of the picture a very long ways. That arm is longer than all others. Plant or animal it really doesn't matter. The significance of this is that it shows signs that it is alive. That is everything, but not to NASA," Scott Waring wrote for UFO Sightings Daily.

Proponents of the idea that the facehugger-shaped formation is alive have provided several names for the object, including Alien, John Carter, Spider and Awesome Martian Space Crab. 

The Mars Science Laboratory (MSL), better known as the Curiosity rover, is celebrating three years since landing on the Red Planet. During that time, the robotic observatory has recorded several strange objects on the surface of Mars. These include a feature resembling a pyramid, which some observers claim is evidence for an intelligent civilization on the Red Planet. 

Another feature recently pictured by Curiosity seems to resemble a woman with long hair and large breasts. This shape appears to be standing, observing the spacecraft from Earth. In another odd image, a nearly-perfect sphere appears to be hovering in mid-air, and a shadow appears beneath the object. 

The search for life on Mars is in the forefront of NASA's investigation of the Red Planet. In July, 2015, the American space agency announced the discovery of an unusual Martian rock, rich in silica, which could potentially house artifacts of ancient life. 

Despite remarkable claims about signs of intelligent life on Mars, most scientists believe these sightings are the result of pareidolia. This psychological phenomenon results in people seeing familiar objects, such as faces and crabs, in objects that have only a passing resemblance to these common sights. One of the best-known examples of this is the so-called face on Mars.

Some researchers believe that pareidolia may have evolved as it provided a means for ancient people to discover order in the seeming chaos of the world around them. 

Despite the spider on Mars, there is still no sign of David Bowie.