Xref: utzoo talk.politics.misc:8521 sci.misc:1132
Path: utzoo!mnetor!uunet!husc6!think!bloom-beacon!athena.mit.edu!jfc
From: jfc@athena.mit.edu (John F Carr)
Newsgroups: talk.politics.misc,sci.misc
Subject: Re: The Last Word on Friedman, Sevener, and Cuba
Message-ID: <3994@bloom-beacon.MIT.EDU>
Date: 24 Mar 88 07:19:16 GMT
References: <3405@bloom-beacon.MIT.EDU> <3895@whuts.UUCP> <3952@bloom-beacon.MIT.EDU> <2136@phoenix.Princeton.EDU> <3980@bloom-beacon.MIT.EDU>
Sender: daemon@bloom-beacon.MIT.EDU
Reply-To: jfc@athena.mit.edu (John F Carr)
Organization: Massachusetts Institute of Technology
Lines: 36

In article <3980@bloom-beacon.MIT.EDU> lazarus@athena.mit.edu (Michael Friedman) writes:
: Mr. Lovell has brought up a very important factor which was ignored in
: the discussion about the visibility of Cuba from Florida - continental
: drift. In order to prove that I did not see Cuba it is not enough to
: prove that it cannot be seen now. It must be proven that it could not
: be seen in, say, 1975, or so. To do this you must prove either that
: Cuba is not moving away from the US due to continental drift, or that
: despite this movement Cuba was not visible even in 1975.
: 
: I eagerly await further postings on this matter.

No need to wait any longer.  

Next on the list of subjects not considered in this discussion:
the doppler shift of light reflected from Cuba due to the motion of 
Cuba relative to Key West and the atmosphere.  It is a well known fact 
that the index of refraction is a strong nonlinear function of wavelength.  
(This is the reason diffraction gratings are preferred over prisms.)
Depending on your assumptions of the velocity and reference wavelength,
doppler shift of light could be important.  And also, we can't forget 
earth tides.  At certain phases of the tide, the velocity difference 
between Cuba and Key West due to tidal deformation of the Earth by the
moon may even exceed the relative motion due to plate motion and deformation
At 'ebb' tide, Cuba and Key West will be pulled closer together by this effect
but have no relative velocity, while at other phases they will be further 
apart but have a larger relative velocity.  Adding to this the fact that 
the Moon was closer to the Earth in 1975 than it is now, and so exerted 
stronger tides, we have the potential for an important contribution to this 
debate.

I request that these topics be addressed by Tim Sevener in his next followup.
I have good ideas about the magnitude of their effect, and I am sure most of 
the scientifically aware people on the net do also, but I request that those 
who have estimates of the magnitude of such effects keep them to themselves 
for a short time as it would be best to have the first response come from Tim 
so there can be no allegations of bias or lack of scientific knowledge.