Over the past two centuries many researchers have claimed to have seen forms of human beings on Mars. These include various forms such as Mahatma Gandhi's face, vegetation and water channels on the Martian surface.
Though Mars is the closest planet in the solar system that may have a possibility of becoming a habitable planet, theories of spotting various forms including faces have been debunked by advanced research. So, is it just an optical illusion? Let us try to find out the reason why people keep seeing various forms on Mars.
The theory of seeing faces got a boost when NASA released an image of a mountain on Mars in 1976. The image was taken by the Viking 1 Spacecraft and it looked like the one having eyes and nostrils. Speculations were rife that an artificial structure was built by an ancient Martian civilization. But later, images taken by Mars Express Orbiter did not show any face-like structure in the mountain.
What is Pareidolia?
When a map program called Google Mars was launched in 2009, which showed compiled satellite images of Mars, various bumps and lumps were seen. Matto Ianneo from Italy claimed to have discovered a bump that looked similar to the face of Indian independence activist Mahatma Gandhi. But the truth is that there was no such face on Mars.
In fact, scientists say it is the result of a condition called Pareidolia, which is the scientific term for seeing various forms including faces when they don't exist in reality. According to Takeo Watanabe of the Boston University Visual Sciences Laboratory, humans have over-learnt human faces so they see them even where they are not present. So, this is a by-product of heightened sensitivity to details of human faces.
In 2007, an image captured by NASA's Mars Exploration Rover Spirit showed the westward view from atop a low plateau. In the image, a structure of a human being wearing a robe and kneeling in prayer was visible. This gave wings to theories of life on Mars. But the truth is that the human seen in the image was a rock. As told earlier, Pareidolia makes the rock look like a human being to the human brain.
Does Mars Have Vegetation and Channels?
Science fiction writer Arthur C. Clarke told in 2001 that he had spotted patches of vegetation including trees in photos taken by Mars Global Surveyor. He also claimed that something was actually moving and changing with seasons and came to a conclusion that it was vegetation.
But the truth is that Clarke had seen 'Araneiforms' which are also called 'Spiders' on Mars. Spiders are only seen on Mars and are formed when dry ice changes from solid to gaseous state in spring. Thus the changes noticed by Clarke were due to seasonal melting of carbon dioxide ice caps on Mars' poles. According to Live Science, carbon dioxide turns into a gas and flows along paths and it looks like branches.
Even canals found on Mars were declared as optical illusions. Reports claim that such forms are seen especially when viewed through poor-quality telescopes. Spectroscopic analysis of the light coming from Mars has proved that there is no water on the surface of Mars.