Re: Speaking of "Buy Jupiter" (was: Arthur C. Clarke question)

wdstarr@[EMAIL PROTECTED]
 (William December Starr) writes:

>In article <nebusj.1205699116@[EMAIL PROTECTED]
>,
>nebusj-@[EMAIL PROTECTED]
 (Joseph Nebus) said:

>> I have a copy of _Buy Jupiter_ for some reason, and

>Speaking of "Buy Jupiter" -- the short story, not the collection --
>see <www.moonvertising.com>, an ad/promotional campaign for Rolling
>Rock beer that seems to involve using an Earth-based laser to write
>messages (impermanently, alas) on the Moon.  Or pretending too; I
>got tired of the site's format rather quickly and left before
>ascertaining how much of it was serious and how much was spoofery.

	Oh, yes, I've noticed those commercials.  I have to figure that 
the scheme is meant to be nothing but a publicity hoax: they'd need 
enough power to make something stand out against the light of the full 
moon, and that with a laser's spread over half a million miles.  

	A 1994 article from Science puts the signal loss reflecting 
from Earth to laser reflector on the Moon and back at about 10^{-21} 
(personal note: !), so the 3 Joule-per-second lasers available then 
required single-photon detection from the receivers: 

	http://physics.ucsd.edu/~tmurphy/apollo/doc/Dickey.pdf

	So barring a surprise development by Chairface Chippendale I'm 
expecting whatever company it is doing it to announce that this attempt 
happens not to have succeeded but thank you for looking at the Moon
anyway.  

-- 
								Joseph Nebus
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