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From: Alexandre Eremenko (no email)
Date: Mon Oct 25 2004 - 18:38:04 EDT
Here is a question to the Lunars experts:
Why do we need a sextant at all??
Just watch for the moment when the moon
"collides with a star" on its normal way
(there are so many stars around!)
and notice this moment on your watch.
It is easy to modify your lunar reduction programs
then to find GMT of this "collisoon".
(The "true distance" at this moment equals to
the corrected "semidiameter". Then take Moon's parallax
into account and that's it!)
I mean, of course the version when no altutudes are measured.
So you have the whole night to look for these collisions.
Few days after this came to my mind, I found that
I was not the first:-)
The method was proposed centuries ago and it is called
"ocultations of the stars by the Moon".
Then why was not this practiced at least as much as
the Lunars were?
I sort of remember someone saying that Lunars give bad
results when the distance is too small... In the case
of occultation the distance is zero.
But why is this so? I mean what is wrong with the method,
and why Lunars are not recommended when the distance is small?
Alex.
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