Occasionally science is all luck and good fortune. Sort of, anyhow. Louis Pasteur said "In the field of observation, chance only favors the prepared mind."

A list of famous and important accidental discoveries:

• synthetic dyes
• penicillin
• antidepressant drugs
• classical conditioning (Pavlov's dogs)
• x-rays
• pulsars
• cosmic background radiation
• gamma-ray bursts
• nylon
• PVC
• neoprene
• teflon
• that microwaves could be used for cooking
• vulcanization
• measuring volume via displacement of a liquid (Eureka!)