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Optical SETI
Some optical SETI sites:
Columbus optical SETI
(COSETI)
Harvard, Princeton
Berkeley
optical SETI
Lick optical SETI
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Pros and cons of optical SETI
Pros
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a pulsed nanosecond laser source can be thousands of
times brighter than a sun
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there are no nanosecond astronomical
background sources that mimic pulsed optical
SETI although
there are cosmic ray artifacts that must be eliminated by coincidence
methods
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SETI optical receivers and associated software may be
cheaper than radio SETI equivalents
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both pro and con: optical receivers view a narrow angular
cone. This means the gain is higher but it is necessary
to be sure that
the field of view takes in the whole planetary system
Cons
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extinction effects in the plane of the galaxy beyond 1000
ly
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as with radio sources must address possibility of Doppler
shift for narrow frequency band signals
Solar arrays for
optical SETI?,
Maser and laser
astronomical sources
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Natural astronomical maser signals can be very powerful.
Could an advanced civilization modulate a natural source?
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