A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Jim Rives
Date: 2020 Jan 30, 08:49 -0800
Venus is a very handy object for lunars these days. I went out yesterday and shot one in a local parking lot. I graphed the results and came up with a
raw LD of 15d 20.8' at 2210GMT. See graph attached if interested.
Then to Frank's Lunar Calculator: DR Lat 43 00.0N, DR Long 71 00.0W IC -2.3, Temp 35F, Pressure 29.95, HoE zero, Calculated altitudes, and my LD observed of 15d 20.8' per above.
So, True LD 16d 11.3' vs Cleared LD of 15d 55.3', or "Error in Lunar" = 16.0'.
If 1 arc min = 4 secs of time, then 16x4 = 64 seconds. Which would make GMT 64 seconds earlier than 2210, or 22h08m56s. Is this correct?
I am not sure what the significance of cos Diff Azm: 0.96296 is. And I don't understand the "Approximate error in Longitude: 8d 00.8' ". That seems huge!
I apologize for running another of my lunars by everyone again, but I think I'm getting closer to finally understanding the whole process.
Thanks in advance to anyone who replies.