Lookups spiked on July 4, 2012.
Evidence of the so-called "God particle," the Higgs boson, was demonstrated by scientists in Geneva.
This prompted worldwide headlines like the New York Times' "Physicists Find Elusive Particle Seen as Key to Universe," and talk of a Nobel Prize.
The announcement confirms a theory explaining how some of the building blocks of matter have mass while others do not.
A boson is a kind of fundamental particle and a Higgs boson is one that can give mass to other particles. The names of the particles come from two scientists: British physicist Peter Higgs, and Indian mathematician and physicist Satyendra Nath Bose, who collaborated with Albert Einstein in the 1920s.
Photo credit: The M74 spiral galaxy from NASA, ESA, and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration