Assessment OICNW-1-1G

Measure the altitude of at least 3 stars

Assessed in MT-4371 Sea Term IV: Marine Transportation


Aboard a ship at sea, given a standard marine sextant, a clear horizon, a clear or partly cloudy sky, and an accurate time, during a single twilight.

Performance Requirements

Behavior Standard
The student will: During assessment, the student shall, at a minimum:

Measure the altitude of three stars and accurately record the times of the observation of each star.

  1. The altitude is within ± 0.5 minutes of arc, after correction for index error, as compared with the altitude measured by the assessor at the same time; and,
  2. The time is within ± 2 seconds of UTC at the time of observation as determined by the assessor.

Supports Table A-II/1 officer in charge of a navigation watch

Competence Knowledge, Understanding & Proficiency Task

Plan and conduct a passage and determine position

A1.01 Celestial Navigation

Ability to use celestial bodies to determine the ship’s position

Measure the altitude of at least 3 stars

Published: 2016-10-28-04:00