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Old December 18th 03, 11:46 AM
Benoit Morrissette
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On Wed, 17 Dec 2003 8:01:23 -0800, DaveC wrote:

On Wed, 17 Dec 2003 1:28:16 -0800, Roger Hamlett wrote
(in message ):


"DaveC" wrote in message
al.net...
How does LST correlate to our terrestrial time? I'm not looking for a
definition, or an explanation that includes angles of the equinox, or

such. I
just want to know if a particular time in LST is fixed in relation to the
clock on the wall, or if it changes over the year, and how to calculate it

or
look it up.

Thanks,

You are really saying, "I don't want a definition", but "I want a
definition"...
A sidereal day, is four seconds shorter then the normal 'clock' day. So a
particular sidereal 'time' arrives four seconds earlier each day (when
compared to a normal clock).
Now the question of calculating it, depends on just how accurate you want to
go?. The simplest way (which is accurate enough for most uses), is to use a
chart, based on this 'drift' between the clocks. One is at:
http://pietro.org.tripod.com/Astro_U...ealVSCivil.htm


Is there a web site where I can enter Longitude and get a chart of LST?
Something done in Java, perhaps?

Thanks,

http://www.jgiesen.de/astro/astroJS/...lock/index.htm
Good night!

Benoît Morrissette