A few weeks ago, Jesse Tarnas, a graduate student at Brown University had suggested in his study that Mars, in its ancient days had sufficient source of chemical energy required for microbial organisms to survive underground.

As the study report surfaced online, many conspiracy theorists claimed that the Red Planet was once home to alien life, and they are quick to conclude that space agencies like NASA are well aware of this fact.

In view of rampant speculations over life on Mars, IB Times India presents five crucial signs which indicate that life once existed on the Martian surface.

The discovery of Cannonball

Scott C Waring, one of the most popular UFO researchers who has been studying alien activities for the past few years strongly believes that Mars had one witnessed a galactic war. A few months ago, after analyzing a video posted on YouTube by a user named 'WhatsUpInTheSky', Waring spotted a seemingly metallic cannonball on the Martian surface.

In a post written on his website 'UFO Sightings Daily', Waring argued that the metallic cannonball spotted on Mars could be the remnants of an advanced ancient civilization that once ruled the Red Planet.

"This is 100% evidence of a war on Mars. This projectile is sitting on the surface above all the wrecked stone structures around it. Fragments of a once civilization is sitting scattered in tiny pieces around this cannonball," said Waring.

However, experts believe that these round structures spotted on Mars could be actually spherules, that naturally occur on the Mars in large quantities.

The shocking revelation made by Brian Cox

In a BBC radio program, Brian Cox, a professor of particle physics in the School of Physics and Astronomy at the University of Manchester assured that alien life forms existed on Mars during the ancient period.

During the talk, the physicist also suggested that humans could actually be Martians who might have reached the earth on meteorites and other space bodies.

"There is one theory that we could be Martians because it is possible that life began on Mars over four billion years ago. It came to the Earth on meteorites so not in spaceships or anything, but on meteorites that got knocked off Mars. There are bits of Mars that land on Earth and the life got delivered to Earth and therefore, we are Martians. It is not the most likely theory but it is a possibility that people discuss," said Cox.

Egyptian styled statue on the Martian surface

A space video journalist named Joe White recently claimed to have discovered a potential proof of alien life which once existed on the Red Planet. Joe White, after analyzing the pictures taken by NASA's Curiosity Rover spotted a structure that looked like a statue on the surface of Mars.

Interestingly, the statue spotted by Joe White seems very similar to the head of an ancient warrior woman. It should be noted that such structures are found abundantly in Egyptian historical sites.

Apart from the discovery of the statue, Joe White had also spotted various anomalies in photos taken by the Curiosity Rover which includes a structure very similar to a bearded man, and a boot lying above the rocks of Mars.

However, after analyzing the claims made by Joe White, experts dismissed these claims and made it clear that it is the peculiar capability of the human brain named pareidolia which is resulting in these visual hallucinations. As per experts, pareidolia will make humans to figure out familiar objects from unknown structures.

The study conducted by Edinburgh researchers

A recent study conducted by a team of researchers at the University of Edinburgh has suggested that rocks near the ancient Martian lakes may contain traces and fossils of creatures, mostly in microbial form.

As per the researchers who took part in this study, sedimentary rocks made of mud and clay in the Martian surface may contain fossils, and it may have formed during the Noachian and Hesperian Periods of Martian history.

These experts also believe that water was very much abundant on Mars, three to four billion years ago. The study report published in the Journal of Geophysical Research also reveals that the findings will help NASA to select a suitable landing spot for their next Mars mission.

NASA discovers organic matter and methane on Mars

The most crucial revelation that substantiated the existence of alien life on Mars came from NASA last June. The United States space agency revealed that they have discovered ancient organic matter and a mysterious presence of methane on the Martian surface.

As NASA made this shocking revelation, alien enthusiasts strongly claimed that the presence of organic matter could be signaling the existence of a glorious extraterrestrial civilization on Mars in the past.

However, NASA revealed that the emission of methane could be produced by various chemical reactions which may be unrelated to life.

"Organic molecules contain carbon and hydrogen, and also may include oxygen, nitrogen and other elements. While commonly associated with life, organic molecules also can be created by non-biological processes and are not necessarily indicators of life," added NASA in its release.