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Old 18-08-2010, 10:53 PM
gary
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gary is offline
 
Join Date: Apr 2005
Location: Mt. Kuring-Gai
Posts: 5,999
Quote:
Originally Posted by DavidTrap View Post
I can keep up with this until the fourth line where you mention HA? What is that. How do you then calculate the longitude from that?
Hi David,

No problem.

HA is the Hour Angle, which is expressed as a time.
So for the object, its HA = LAST - RA
i.e HA = 20:26 - 16:43 = 03:42
(Apologies, in the prior post I made a typo for the LAST, as 20:36 rather than
the correct time of 20:26 - but the result was correct).

We know that there are 24 hours in 360 degrees.
Thus 1 hour = 15 degrees.

Thus 03:42 converted to degrees is 3.71 * 15 = 55.66
The Longitude at Linville is 152.274E.
Thus 152.274 - 55.66 = 96.61E
which is equivalent to 96:36E

Best Regards

Gary
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