A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Frank Reed
Date: 2019 Dec 1, 12:16 -0800
Either of these is OK in certain contexts. In the late 20th century, the terminology of celestial navigation has reached a point where it over-constrained the concepts and the principles. In certain technical settings, LHA is the hour angle of a celestial body constrained so that it always runs west. Thus an LHA of 359° corresponds to an object that is just one degree east of the observer's meridian. In this same narrowly-defined setting, the common hour angle referred to as "t" is measured east or west and may be ambiguous in that sense. The concept of Hour Angle (and the name) have been around much longer than these over-constrained definitions. I usually just call the meridian angle plain-old "Hour Angle". But it is certainly a "local" hour angle and so it can also be fairly referred to as "LHA". Take your pick -- just be careful to describe what you mean.