Celestial Navigation · Amplitudes — Due East/West
When a body's declination is 0° (e.g., the sun at the equinox), its amplitude is 0°, meaning it rises:
- ADue south
- BIn the southeast
- CIn the northeast
- DDue east and sets due west✓ Correct
Explanation
Amplitude is the angular distance of the rising or setting point north or south of due east/west. With zero declination the amplitude is zero, so the body rises bearing exactly 090° and sets bearing 270°, regardless of the observer's latitude.
Authority: Bowditch (Pub. No. 9), Amplitudes
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