A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Frank Reed
Date: 2016 Oct 31, 10:10 -0700
Here's an example of sights from Stellarium. I've selected a location which you can see in the image below called spoiler-alert1.jpg. Do not look at that image until you're worked out the sights and fix. You are sailing from Massachusetts to Bermuda. Your DR position is 37° 15' N, 66° 30' W, and you're not moving. You have taken sights of Sirius, Aldebaran, Regulus, and Jupiter before sunrise. Altitudes and times are shown in the attached screen captures from Stellarium. Remember, the only altitude correction you require is refraction. Don't be misled by the notation showing an observer height of 25m. That's not height of eye for altitudes; it's height of observer for parallax-based changes in body position which are completely insignificant for these sights.