What discovery would weaken the primordial soup hypothesis of the origin of life?

lightning was common on early earth.
earth’s early atmosphere contained carbon dioxide, water, and trace gases.
earth’s early oceans were warm and shallow.

Lightning was common on early Earth is the discovery which would  weaken the primordial soup hypothesis of the origin of life.

Explanation:

The hypothetical conditions on which the theory regarding the origin of life is dependent is the Primordial Soup theory. Proposed by Alexander Oparin, this theory states that objects like hydrogen, water vapor, carbon etc. Forms the living beings on Earth. This theory though doesn't talk about the impact of uncommon asteroids in life formation on Earth.

The atmosphere of Earth had lighting and asteroid as common phenomenon and thus the uncommon phenomenon of asteroid would weaken this hypothesis.  

your answer is "the 1950's"