Celestial Navigation · Hour Angle — LHA West Longitude
The GHA of a body is 200°00' and your assumed longitude is 60°00' W. What is the local hour angle (LHA)?
- A320°00'
- B260°00'
- C140°00'✓ Correct
- D200°00'
Explanation
In west longitude, LHA = GHA − west longitude = 200° − 60° = 140°. (East longitude would be added.) LHA is measured westward from the observer's meridian to the body's meridian.
Authority: Nautical Almanac; Bowditch (Pub. No. 9), Hour Angle
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