Charles Townes was an American physicist at the University of California, Berkeley, who was awarded the 1964 Nobel Prize in Physics with Nikolai Basov and Alexander Prokhorov for independently working out the theory of the maser and, later, the laser. He built the first maser in 1951.

 

Townes was also a pioneer in microwave and infrared astronomy and led the team at Berkeley which, in 1968, discovered water and ammonia molecules in interstellar space (see interstellar molecules). He has a long-standing interest in the possibly of optical SETI and while at the Massachusetts Institute of Technology in the early 1960s was the first, together with R. N. Schwarz, to suggest the possibility of using lasers for interstellar communication. He was later involved in a project, funded by the Planetary Society, to search for artificial laser pulses coming from a variety of sources, including nearby stars, globular clusters, and external galaxies.