NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Pike
Date: 2016 Aug 28, 04:19 -0700
Frank, I was going to say “What goes up must come down” but that’s not true with space craft is it? The chances are that the snap is taken with a telephoto lens of unknown specification, so it’s probably farther away than it looks. Hopefully horizontal angles are displayed the same as vertical angles, but we’ve got to be careful with simultaneous equations that we don’t end up proving 0=0. We need to look for a discontinuity. How about measuring horizontal angles isn’t affected by earth curvature, but measuring vertical angles will be in this case. The spacecraft is still higher than you think, because there’s a distance below the horizon, and this is a function of range. That gives us our break. It’s just a question of setting up the equations. Working on it. DaveP