ASA 117, Basic Celestial Endorsement

Demonstrate the ability to apply basic celestial navigation theory and practice to determine latitude and longitude at sea using a sextant and Nautical Almanac.

SKILLSA Certified Sailor will have successfully demonstrated their ability to perform the following…

1. Understand the terms and theory of Basic Celestial Navigation taught in this course and course text (Basic Celestial Navigation)

2. Convert between standard time and zone time to GMT/UT in either direction.

3. Calculate the zone time at a given longitude.

4. Determine the times of sunrise, sunset and civil twilight for a vessels position.

5. Know the parts, principals and operation of a traditional sextant.

6. Determine altitudes of the Sun and Polaris by a traditional sextant.

7. Obtain Latitude and Longitude at noon (LAN) by applying the sextant corrections for conversions of the raw sextant altitudes (hs) of the Sun to the true celestial altitudes (HO) of the Sun.

8. Determine the vessels latitude and Estimated Position at morning and evening twilight by means of the altitude of Polaris.

9. Plot latitudes and EPs on a chart.

10. All of the above are accomplished by a traditional sextant and a Nautical Almanac without the use of a programmed calculator or computer.