My favorite photograph

When I was in school, my teacher spoke to us about Nazca lines. This lines have an unknown origin. People think that lines was created by aliens, but that it´s just a supposition. I like very much this mysterious things, so I decided to search some photos on the internet after that class. The photos was published by Erich Von Däniken in 1968 in the book Remembers from future. I choose one in particular, called The Astronaut, that is the most controversial figure of all. According to a myth from the civilization of Lake Titicaca, say that the astronaut is a "being coming from the stars" whose intention was improve a savage giant race of the past by miscegenation. 

Interesting, isn't? A lot of amateurs say that the image is a proof of aliens existence in earth. Others more sceptic say that is just a representation of a man. What do you think about?