Celestial Navigation · Assumed Position
When using Pub. No. 229 sight reduction, the assumed longitude is chosen so that:
- AIt equals the DR longitude exactly
- BThe declination is zero
- CThe local hour angle (LHA) comes out to a whole degree✓ Correct
- DThe altitude is exactly 45 degrees
Explanation
The assumed longitude is picked near the DR so that, combined with GHA, the LHA is a whole degree (table entry). The assumed latitude is the whole degree of latitude nearest the DR.
Authority: Pub. No. 229, Sight Reduction Tables for Marine Navigation
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