
NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Raw data for bubble
From: Bill B
Date: 2007 Mar 22, 18:48 -0400
From: Bill B
Date: 2007 Mar 22, 18:48 -0400
Bill Noyce wrote: >> I think the intent is to observe until the predicted h occurs, and >> record the resulting GMT. From that and the matching LHA you compute >> GHA and Longitude. Right? And you use the graphical method to >> interpolate to hit the desired h exactly. > Bill responded: > You would have to ask Peter about that. My impression is once he had the > time of transit, he computed Hc. Any difference between Hc or Ho was > plotted east/west from AP for longitude. If understand Peter's method, I missed one part in my answer. Peter wants the observation to be exactly at the pre-computed time. That can be a problem in practice. By starting before the exact time he derives two benefits: --He has points he can fit to a slope to find for the best estimate of Hs, H or Ho and identify outliers. --If he missed an observation at the exact moment, he can locate that moment on his time axis then the plot line of Hs, H or Hc. Bill B --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To unsubscribe, send email to NavList-unsubscribe@fer3.com -~----------~----~----~----~------~----~------~--~---