Von Daniken was in the early 70's and he wrote several books. THey tended to get more and more fantastic as he pressed his theory into every conceivable anomaly.
The basic theory was that earth was helped along by alien visitors. He never answered the two basic questions that formed in my mind:
1- Why would they bother?
2- Why would they stop?
Still, his petroglyphs showing similar figures from disparate places with apparent helmets and hoses were interesting, to say the least.
But everything he attributes to ancient astronauts could be equally explained by Hancock's Legacy Civilization....and without resorting to outer space.
Von Daniken did, I seem to recall, have an interest in what technology would seem like to primitive people. Our science would be their magic and he was of the opinion that religion arose from that basic misunderstanding.
I think it was V.D. who came up with an interesting intellectual exercise. You can try it if you like.....I've done it and it is a bitch. I can't recall exactly what his parameters were but it doesn't matter, you'll get the idea.
Imagine yourself living in a forgotten valley in New Guinea. You live a basic stone age hunter/gatherer lifestyle. Your language consists of about 600 words....mainly environmental; tree, rock, bush, fire, water, rain, thunder, lighting, bird, snake, words for different animals and fish, words for some of the people in the tribe, etc. You carry a flint-tipped spear. You have an animist religion which thinks that spirits inhabit trees and animals.
One day you are out hunting a few miles from your 'village' when you hear a dreadful noise. Curious, you head towards the sound and peeking out from behind a rock you see a large jet helicopter just powering down its rotors after landing. You are terrified but can't look away or run away.
As you watch, ten people get out all dressed in orange (or any color you like) flight suits with white helmets. You note this symbol on the side of the helicopter.
The crew spreads out conducting various scientific tasks. One shouts and points at something on the ground and another comes running with an automatic rifle which he proceeds to fire 3 times. Then he goes over and picks up the body of a snake, shakes it at the person who yelled, and tosses it away.
The crew spends several hours at the landing site until the commander says something and they all pack up their gear and get back on the chopper. Then with a noise you have never heard before the chopper lifts off and the jet engines fly it away.
You stay where you are for a few moments and then wander out into the field. You find 3 spent shell casings and the body of the snake, with wounds of such a nature that you cannot equate them to your spear. Aside from the casings, you find some plastic wrappings and other trash left behind and duly pick these up to bring back to your tribe.
Now, here is the assignment. Describe what you have just seen to the tribal elders using only the basic language skills that you possess and the handful of artifacts that you picked up.