[AZ-Observing] Re: telescope troubles

Time is much more complex than many people realize. Astronomical time 
is even more so.

Take for example: We have MST that everyone around understands, no 
problem. Then we have local mean time, sidereal time, Universal Time 
and of course Julian Date.

Since most if not all astronomical dates and times are in Julian 
Date, it is important to understand it. Given a Julian Date and 
trying to find local time is easy to get it wrong. Julian Date starts 
at noon GMT or UT.

A JD = 2,454,129.511 is just after midnight on 29 January 2007 UT 
(UT= 00:15:50) which is 17:15:50 MST on 28 January 2007.

Jeff

At 16:21 -0700 1/29/07, Rick Tejera wrote:
>You would think that engineers would adhere to the KISS principle. I think
>the reasoning is that by using the reverse offset, they avoid having to deal
>with negative numbers, at least for the largest segment of their markets.
>Although I'd think that for people smart enough to program these things,
>dealing with a negative would be awfully simple. If they think they are
>making easy on the EU by not having to them think about negatives, They
>should consider that a simple mention in the Destructions that "ALL TIME
>ZONES in North America are Minus". Of course this presumes the EU will
>actually read the destructions.
>
>Enough ranting, I gotta deal with time zone illiterates all day at work: I
>need my package in Honk Kong by 0800 tomorrow morning. It usually comes as a
>surprise that that is only 4 hours away.
>
>Rant mode off
>Rick Tejera
>President
>Editor SACnews
>Saguaro Astronomy Club
>Phoenix, Arizona
>saguaroastro@xxxxxxx
>www.saguaroastro.org
-- 
Jeff Hopkins
HPO SOFT
Counting Photons
http://www.hposoft.com/Astro/astro.html
Hopkins Phoenix Observatory
7812 West Clayton Drive
Phoenix, Arizona 85033-2439 U.S.A.
www.hposoft.com
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