The experiment carried out in 1953 by Stanley L. Miller and Harold C. Urey proved that life originated from inanimate elements. They made an artificial atmosphere that resembled that of the early planet; it contained ammonia, hydrogen, and other gases believed to have existed during the prehistoric era of the world.
The temperature of this mixture of gases was held just below 100 ° C. In addition, sparks were produced to mimic lightning, which was also considered to occur frequently at the time. At the conclusion of the test, he was able to produce 11 of the 20 amino acids needed for life.