Optical SETI Map Conferences Map Illustrations Map Photo Galleries Map Observations Map Constructing Map
Search Engines Contents Complete Site Map Tech. Support Map Order Equip. Map OSETI Network

Search WWW Search www.coseti.org Search www.oseti.net Search www.photonstar.org Search www.opticalseti.org

colorbar.gif (4491 bytes)



Reflections on Forty Years of Optical SETI --
 Looking Forward and Looking Backward


Charles H. Townes


Picture by Tom McDonough, The Planetary Society, 1993



When, in early 1961, interstellar communication with lasers was first discussed, it was met with interest but not enthusiasm.  The scientific community was thinking of laser powers in the kilowatt range (which had not yet been actually achieved) and telescopes of maximum diameter 200 inches.  Now there are lasers of average power 106 watts, pulsed power 1015 watts, and telescopes of diameter 10 meters.  Just what technology an advanced extrasolar civilization would have is still debatable, but on earth communication with lasers is growing rapidly and now "Optical SETI" seems to many a likely  prospect.  In addition to increased power and variety of lasers, with expectation of further growth, the easy use of short pulses alleviates the need for high spectral resolution required by CW laser communication, and gives high signal to noise  ratios.  Such changes in our own technology and views over only a few decades obviously stimulate open-mindedness about  the state of technical developments and communication in any external civilization.  And what are the resulting speculations?



Optical SETI, 1961, lasers, communications, technology, history.



Principal Author Biography

1915  Born in Greenville, S.C.
1935 Receives a B.A. and a B.S. from Furman University.
1937 Receives an M.A. from Duke University.
1939 Joins Bell Labs on West Street, N.Y.C., after receiving his Ph.D. degree in physics from the California Institute of Technology.
1948 Becomes an associate professor of physics at Columbia University.
1949 Meets Arthur L. Schawlow, who comes to Columbia University on a fellowship and works as a research assistant to him.
1950 Becomes a professor of physics at Columbia and executive director of the Columbia Radiation Laboratory.
1951 Conceives if the idea of a maser (similar ideas occur independently to A. Prokhorov and N. Basov in Moscow and J. Weber of the University of Maryland).
1952 Becomes chairman of Columbia's Physics Department.
1953  Builds the first maser with J. P. Gordon and H. J. Zeiger at Columbia.
1955 Co-authors the book Microwave Spectroscopy with Schawlow.
1956  Serves as a Bell Labs consultant in the field of solid-state masers.
1957 While serving as a consultant to Bell Labs, begins working with Schawlow on the principles of a device -- the laser -- that could operate at wavelengths a thousand times shorter than the maser.
1958 Proposes with Schawlow in a paper published in the December Physical Review that the principles of the maser could be extended to the optical regions of the spectrum using an incoherent pump source.
1959-61 Becomes vice-president and director of research for the Institute for Defense Analysis in Washington, D.C.
1960 Receives with Schawlow a patent for the invention of the laser. The first working laser is built by Theodore Maiman at Hughes Aircraft Company using ruby at 0.69 microns.
1961 Co-authors paper with R. N. Schwartz titled: "Interstellar and Interplanetary Communication by Optical Masers" an April issue of Nature.  This is the first description of the optical approach to SETI.
1964 Shares the Nobel Prize in Physics with A. Prokhorov and N. Basov of the Lebedev Institute in Moscow for "fundamental work in the field of quantum electronics which has led to the construction of oscillators and amplifiers based on the maser-laser principle."
1966 Becomes Institute Professor at MIT.
1967 Becomes University Professor of Physics at the University of California at Berkeley.
1986 Becomes University Professor of Physics, Emeritus, at the University of California at Berkeley.
1993 Participated in SPIE's OSETI I  Conference.
2001 Will participates in SPIE's OSETI III Conference which marks the 40th anniversary of Optical SETI.



Principal Author Affiliation

Space Sciences Laboratory
University of California,
Berkeley, CA 94720-7450
Email: cht@isi16.ssl.berkeley.edu


RealAudio RealPresenter
Reserved for Talk Reserved for Slideshow

Home Glossary
SPIE's OSETI I Conference SPIE's OSETI II Conference
SPIE's OSETI III Conference
The Columbus Optical SETI Observatory
Copyright , 1990-2006 Personal Web Site:
Last modified:  10/28/06
Contact Info