What evidence is there to support the hypothesis of panspermia?

The evidence to support that hypothesis is rather limited, but does include the presence of organic compounds in recovered meteorites. Before life, there was metabolism, and before metabolism, there was the formation of organic molecules from the raw materials available on Earth in its early, cooled-down stages, with lightning supplying the initiating energy. Experiments have been done in the lab by firing a spark through a gas mixture similar to that which is thought to have been in our early atmosphere, and the result was the formation of some of the simple amino acids, the building blocks of life. Life itself could easily have been the introduction of electrical energy into those early molecules.