A somewhat irreverent definition of serendipity is: Serendipity is when you want to go fishing, dig for worms, and strike oil. If this ever actually happened in real life, there are many who would bemoan the black goo and their inability to catch fish. Only a few would recognize the value of the black goo.
The role serendipity plays in science is often overlooked, but sometimes scientific discovery is like this definition. Serendipity plays an important part, but the scientist must take advantage of the lucky break to make a discovery. Examples of serendipitous discoveries in science abound. Below are a few examples from the history of physics and astronomy.
Oersted and Electromagnetic Effects
In 1820, Hans Christian Oersted performed an electrical demonstration for a class he was teaching. The demonstration used a battery to run an electric current through a wire. Serendipitously someone had left a magnetic compass nearby. When Oersted closed the switch on his demonstration, an electric current surged through the wire. The magnetic compass needle started behaving strangely by jumping in response to the current.
Oersted could have ignored the black goo by declaring the compass broken and tossing it in the trash. Instead he investigated further and discovered a long sought connection between electricity and magnetism. Electric currents produce magnetic fields. Other workers built on Oersted's discovery until Maxwell tied everything together with his famous equations.
In this case Oersted had been prepared for his serendipitous discovery, because he had been one of the physicists searching for the connection between electric currents and magnetic fields. The lucky combination of a cluttered lab and a prepared mind secured Oersted's place in the history of physics.
Röntgen and X-Rays
In 1895 Wilhelm Conrad Röntgen was studying electrical discharges in gasses using a cathode ray tube, which is similar to the picture tube in an older TV or computer monitor. In the process of this work Röntgen discovered X-rays. Among other uses, X-rays are one of the major tools used for diagnostic medical imaging. While doing basic research in physics, Röntgen serendipitously discovered an important medical diagnostic tool.
If he had been specifically searching for a way to make medical diagnostic images, or if he had not further investigated strange effects he noticed, Röntgen would likely not have discovered X-rays.
Bell-Burnell and Pulsars
In 1967 Jocelyn Bell (now Bell-Burnell) was a student worker for Anthony Hewish on a large radio observation project. They were studying scintillation (the same effect as stars twinkling) of radio waves caused by interplanetary gas and dust. She noticed what she called "a bit of scruff" in her data. Bell-Burnell's fellow students told her to ignore the scruff, finish her project, and graduate. She chose to ignore the well meaning advice instead of the scruff. For her efforts, she discovered pulsars, which turned out to be the neutron stars that had been predicted more than 30 years earlier but never found. After her discovery, it turned out that a few other astronomers had observed similar effects in their data, but ignored them.
Oersted, Röntgen, and Bell-Burnell all found the equivalent of black goo in their data, while looking for something else. Their reward for not going fishing and instead investigating the nature of the black goo was the scientific equivalent of finding oil - a major new discovery.
How many scientists missed out on an important discovery because they ignored the black goo or scruff in their data?
Further Reading:
Hewish, A. Bell, J. et al., 1968, Nature 217, 709.
Oersted's Electromagnetic Effects
Physics Nobel Prize Winners 1901 to 1905
Paul A. Heckert - I have a Ph.D. in astrophysics, over 30 years experience teaching physics and astronomy, and over 60 published research articles.
