Question about Light?

Radio and light travel at the same speed

To be pedantic, only through a vacuum...
Light, with less penetrating ability due to its smaller wavelength, will be
slowed down by constant absorption and re-emission by the medium's
molecules. Radio waves will go straight on past.

Space isn't quite a vacuum, so the speed of light may be slightly lower than
the speed of radio waves. Not a factor of 100 though.

Maybe we should use a charged particle beam laser and start blasting some of
these new planets and see if we wake anyone.


"Alexander Schreiber" wrote in message
m.de...
Micky wrote:
I was reading somewhere that they made the first light antenna. I
suppose
that would make it 100's of times quicker than radio signals.?
I know we have 100's of antenna's looking for readio signals from other
planets but do we have any looking for this type of signal already.
What if Aliens only ever used this type of signal or a simular type for
communication, has it
ever been tested for.?
If I were an intelligent being surely it would make sense using a
technology
that is the speed of light rather than radio.

Radio waves _are_ travelling at the speed of light.

A much more likely reason for using light in deep space communications
would be using lasers for the extremly tight beam that lasers allow,
which would enhance transmission privacy (anybody wanting to listen in
must be close enough to the laser beam to intercept parts of it (not
everything, since that would be noticed) and one might be able to cross
larger distances with less power (depends of how power efficient
communication lasers might be compared to radio), although you need to
able to do _very_ precise targetting. Oh, and things like dust or rocks
between you and your communication partner will be _really_ annoying.

Regards,
Alex.
--
"Opportunity is missed by most people because it is dressed in overalls
and
looks like work." -- Thomas A.
Edison


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