The Search for Extraterrestrial Intelligence (SETI) in the
 Optical Spectrum

Welcome to this Web site, the first on the World Wide Web dedicated to promoting the Optical Search for Extraterrestrial Intelligence.  Here you will find a different approach to The Search For Extraterrestrial Intelligence.  The Optical Search For Extraterrestrial Intelligence, otherwise known as Optical SETI (OSETI), seeks to detect pulsed and continuous wave laser beacons signals in the visible and infrared spectrums.  The optical approach to SETI using continuous wave laser beacons was first proposed by Schwartz and Townes in 1961, one year after the laser was invented and two years after Cocconi and Morrison proposed the microwave approach to SETI.

The Columbus Optical SETI (COSETI) Observatory is a pioneering prototype observatory, the first in North America, located in Bexley, Ohio, USA, just four miles from downtown Columbus and close to Port Columbus International Airport.  Bexley is the place made famous by syndicated columnist and best selling author Bob Greene.  The aperture size of the telescope employed by the observatory is 10" (25.4 cm) -- somewhat smaller than those huge microwave radio dishes we are so used to seeing in TV programs and movies about ETIs!  The COSETI Observatory has been designed to detect both attention-getting continuous wave and pulsed laser beacon signals.

Beginning in the summer of 1990, Optical SETI was promoted via postings to Internet newsgroups and from October 1991 till December 1997, this was assisted by a Bulletin Board System (BBS).  This Web site was first launched in April 1996 on CompuServe, followed shortly by two other associated linked sites on Sprynet.  These three Web sites were consolidated and ported over to Netwalk under the domain name www.coseti.org in August 1997, from which time it has grown substantially.  The COSETI Observatory Web site contains an extensive amount of documentation about Optical SETI -- mainly material that has been produced since the summer of 1990, when Stuart Kingsley first started his Optical SETI research activities.  The COSETI Web site is also the means by which the observatory will distribute observational data.  It is intended that real-time data will be put out over the Internet.  Later, remote control of the observatory over the Internet may become possible.  In the meantime, activities here may be monitored, from time to time, via several WebCams.

If you have been knowledgeable about SETI for some time or have seen the movie Contact (the reader is highly recommended to see this wonderful film), you will be aware that until late summer of 1998, little or nothing had been said by the "official" Microwave SETI (MSETI) community to indicate that there was indeed a sensible optical approach to SETI.   This Web site has sought to redress this oversight and show that not only is OSETI a viable scientific endeavor, but that it is more likely that ETIs would use lasers for their interstellar SETI-type free-space communications than radiowaves.  These very technically sophisticated civilizations, if limited to Electromagnetic SETI and the speed of light -- an assumption that is obviously debatable, would employ narrow targeted beams rather than a quasi-broadcast approach which is so energy inefficient.  Unfortunately, the optical approach to SETI, for reasons that are described herein and which are largely due to the Project Cyclops Report, has suffered over  25 years of neglect, particularly in the United States.  Find out why the pioneering work on observational Optical SETI was left to the Soviet astrophysicists, Shvartsman and Beskin.

For the past quarter of a century, popular books and articles about SETI have said little if anything about the benefits of lasers for free-space interstellar communications during a time when we terrenes have been developing such technology for more down-to-earth applications.  This period of time coincides almost exactly with the duration of my career in photonics since starting my post-graduate studies in Electronic and Electrical Engineering at University College London, England.  The COSETI Observatory has consistently maintained that the strong opposition to Optical SETI was scientifically illogical, and clearly, this Web site has helped other SETI scientists to see the light; be it ultraviolet, visible or infrared!  SETI on planet Earth has suffered from the "cult of personality", and up to 1998, politics have prevented a more open discussion of its efficacy.  Of course, this move to the optical spectrum was really inevitable if one believed that ETI signals would not be found in the microwave spectrum.  A negative result for the microwave search was bound to cause a reexamination of the microwave rationale for SETI.

The question has always been very basic -- "Would ETIs use hot photons (visible or infrared) or warm, fuzzy ones (microwaves) and would they have the advanced technical skills available to fully make use of the very high gain potential of laser transmitters?".  Within these pages I have aimed to prove that "hot photons" are far superior for wideband interstellar communications.  By this means, I hoped to encourage other professional and amateur scientists to conduct their own OSETI research.  This spring, the COSETI Observatory launched an associated E-Commerce site to assist others in constructing their own Optical SETI observatories.  Please drop me a line if you have or are about to start your own OSETI research.  Contributions of OSETI articles and data to this web site from scientists, engineers and enthusiasts are requested.  Because Optical SETI is beginning to become very fashionable, members of the print and electronic media are now giving greater exposure to this endeavor.  If you are from the media and undertaking background research on this topic, you can reach me via my CONTACT INFORMATION page.   Please take your time in reviewing this site for both information about the COSETI Observatory and for links to other Optical SETI Web sites.

As mentioned above, during the summer of 1998, a major change took place within the SETI establishment.  This came after a period in which opposition to Optical SETI appeared to be softening.  The SETI Institute and The Planetary Society now consider Optical SETI to be a viable approach, with the major activity being directed at detecting pulsed laser beacons.  Even before the American SETI community came around to support OSETI, various groups in Australia had commenced their own research activities.  The pulsed beacon approach is based mainly on the ideas of photonics pioneer Monte Ross.

The Director of the COSETI Observatory has arranged and chaired for SPIE (The International Society for Optical Engineering), two international conferences on Optical SETI.  A third conference, scheduled for January 2001, is presently in the planning stage.  This conference will mark the 40th anniversary of Optical SETI, and the new Millennium we see the start of a new Optical SETI age.  It is confidently expected that by the year 2005, most SETI activities (by shear numbers and level of funding) on this planet will be of the optical kind!  Documentation relating to the proceedings of the OSETI I and OSETI II conferences and a "call for papers" for the OSETI III conference, may be found on this site.  RealAudio files from the first and second conferences are also available for review on this site.  Stuart Kingsley is also the chairman of The SETI League's new Optical SETI Committee and a board member of The Laser Museum & Space Signal Observatory (LSSO).

The year 2005 is also about the time that NASA was originally scheduled to launch the Next Generation of Space Telescope (NGST).  Mankind should be planning now for space telescopes to be equipped with instrumentation to undertake OSETI observations in the infrared and ultraviolet regions of the spectrum, for which the earth's atmosphere is not transparent.   The Hubble Space Telescope (HST) could also be retrofitted for Optical SETI.  Look out for a link here to be posted in the near future concerning a petition to NASA Administrator, Dr. Daniel S. Goldin, for serious consideration to be given to instrumenting the HST and NGST for both monochromatic and pulsed beacon OSETI.  Ground-based Optical SETI observatories may not discover a laser signal for the simple reason that the atmosphere is opaque to the interstellar laser wavelengths employed by ETIs.  If ETIs are benign and do not wish to destabilize the targeted civilization, they may use the target's atmosphere as a "safety blanket".  This would ensure that the discovery of the fact by the receiving civilization that it is "not alone" is delayed until that society is more mature and has space-based observatories.  Of course, high altitude balloon-based telescopes could also extend our window through the optical part of the electromagnetic spectrum.

Please note that this Web site and the activities of the COSETI Observatory are funded by the income from my professional photonics day job and that I have no official (translation -- paid) position with the SETI community.  For the moment I am just a SETI enthusiast!  I say this as a way of encouragement to young people who often email me to inquire as to "How they can get into SETI".  A new idea or an old idea (as in this case) that has languished around for some time often needs a champion -- a person that will provide a little nurturing before the idea gains acceptance in the wider community.  This has been one such occasion.  Perhaps now we will have success in mankind's search for the answer to that ultimate question "Are we alone?".  I have little doubt that in time it will be discovered that we are just one of many intelligent species within our own galaxy.  Whether any of these species uses a technology as crude and slow as "free-space interstellar laser communications" is quite another question and one that will be hotly debated for years to come.

For the latest popular media publications about Optical SETI, see the December 1998 and June 1999 issues of Sky & Telescope, the August 30, 1999  issue of Time Magazine and the September 1999 issue of the Smithsonian Air & Space Magazine.  A briefer version of the June 1999 Sky and Telescope article may be found in the Encyclopedia Britannica.  Also see recent issues of The Planetary Society's Bioastronomy News and the SETI Institute's SETI News.  Click here for a more extensive list of media publications about Optical SETI and The COSETI Observatory.

Dr. Stuart A. Kingsley
Director, The Columbus Optical SETI Observatory
Revised: July 30, 2000


Recent, historic gathering of OSETI researchers.

Recent, historic gathering of OSETI researchers in Hawaii.
Marcy, Cobb, Kingsley, Werthimer, Howard, and Ross.


 The Third International Conference On Optical SETI