Retrospective Optical SETI

The following is a quotation from my "Conclusions" chapter in the 1992 EJASA article on Optical SETI, page 59.

EJASA - Part 9

"There is probably a case here for an automated retrospective historical study of stellar spectrographic plates to see if ETI signals actually exist and are on record.   It is quite possible that anomalous spectral lines will be found in the record, signifying laser transmissions, but which had previously been overlooked, fogged the film, saturated the recording media, been mistaken for natural bright emission lines, or put down to "technical problems with the spectrographic equipment".  It would not be the first time that a major scientific discovery had been missed for lack of attention and curiosity.  There does appear to be some doubt as to whether C.W. ETI signals, if present, would have been accidentally detected during conventional optical astronomy and recognized for what they were."

Related Materials:

• National Solar Observatory

• The Optical Spectrum & Laser Transitions

• Solar-Type Spectra & Fraunhofer Lines

• Fraunhofer Lines

• Fraunhofer Lines (9006-025)

• Atmospheric Transmission