Rocks From Mars Found By Opportunity Rover Puzzles Scientists [PHOTOS]

A mysterious occurrence on the surface of Mars has left scientists scratching their heads. After ten years of exploring the red planet, the Mars Exploration Rover named Opportunity came across a rock that puzzled experts.

Huffington Post reports that the mysterious rock appeared in front of the rover a couple of days ago. Upon seeing the rock, researchers went back and studied the images taken before the occurrence and were surprised to see that the rock was not there before.

In an article on Discovery, the rock was named "Pinnacle Island" by the NASA Mars Exploration Rover lead scientists Steve Squyres. Squyres said, "It's about the size of a jelly doughnut. It was a total surprise, we were like, 'wait a second, that wasn't there before, it can't be right. Oh my god! It wasn't there before!' We were absolutely started."

The sudden appearance of the rock was confirmed after examining the images taken by the rover's panoramic camera Sol 3528 and Sol 3540.

To view the images taken by the two cameras, click here and here.

NASA theorized that the appearance of the rock might have been caused by the rover hitting a rock as it maneuvered its way to its current location, or, the rock may have landed there caused by a meteorite impact.

Researchers believe that the first theory is more likely to happen.

However, examination of "Pinnacle Island" revealed that it has a unique chemical characteristic, RT.com reports. It exhibits high levels of sulfur, magnesium, and manganese. According to scientists, the manganese level of the rock is significantly higher than anything they have studied in Mars.

Of course, this isn't the first time researchers came across a surprising discovery during their decade-long exploration of Mars. In December of last year, the rover came across signs of an ancient freshwater lake that may have supported life. A couple of months before this discovery, the rover found traces of water in the Martian soil.  

As Squyres puts it, "Mars keeps throwing new stuff at us!"