# MT-2222

## Celestial Navigation

### Course Description

This course covers the requirements of the STCW Convention. The course covers the theory and practice of navigation necessary for the effective and safe navigation of a vessel, including the use of charts, position fixing by celestial observations and the extraction of information from relevant navigational publications. It introduces and focuses on the theory and practice of the use of observations of celestial bodies for determining lines of position and checking compass errors. [Lab time required]

This course consists of three 1-hour lectures and one 2-hour lab per week for a semester with practrical assessments and a comprehensive final examination.

### Entrance Requirements

Successful completion of MT-2121 *Deep Sea Navigation*.

This course serves as a pre-requisite for MT-3371 *Sea Term III* / MT-3372 *Commercial Sea Term*.

### Learning Objectives

**Demonstrate knowledge and understanding of the following STCW elements:**

- OICNW-A1.01 Use celestial bodies to determine the ship’s position
- OICNW-A1.07 Ability to determine errors of the magnetic and gyro-compasses, using celestial means

### Topics

#### Lecture

- The Marine Sextant
- Sextant Principles
- Sextant Altitude Errors
- Sextant Altitude Corrections for True Altitude

- The System of Celestial Coordinates
- The Celestial Equator (Equinoctial) System of Coordinates
- The Celestial Horizon System of Coordinates
- The Navigation Triangle

- Navigational Astronomy
- The Universe and Preliminary Considerations
- The "Celestial Sphere" and Apparent Motion
- Real motions of the earth in solar system
- Apparent Motion of the Sun, Moon, and Planets
- Lunar and Planetary Configurations.

- Review Time
- Introduction, Basic Concepts, Time Scales, and Expressions of Time
- Solar Time -- Apparent Time, Mean Time, and the "Equation of Time"
- The Relationship between Time, Longitude and Hour Angle
- Standard Time and Time Zones
- Watch Time and Chronometer Time
- Sidereal Time

- Time and The Nautical Almanac
- Determination of Positions of Celestial Bodies of the Celestial Sphere
- Finding Greenwich Hour Angle (GHA) and Declination of the Sun and Moon
- Time Diagrams.
- Time Zones, Dateline and ETA Determination

- Rising and Setting Phenomena
- Calculating the Time of Sunrise, Sunset, and Twilight's
- Time of meridian Transit

- Observations for Latitude
- Meridian Altitudes of the sun at Lower Transit
- Determination of Latitude.

- Sight Reduction
- Use of H.O. 229 Sight Reduction Tables for Marine Navigation for Determination of Compass Error – SUN
- Use of H.O. 229 Sight Reduction Tables for Marine Navigation for Determination of Compass Error – Stars and Planets
- Use of H.O. 229 Sight Reduction Tables for Marine Navigation - SUN
- Use of H.O. 229 Sight Reduction Tables for Marine Navigation - Stars
- Use of H.O. 229 Sight Reduction Tables for Marine Navigation – Planets

- Celestial Lines of Position
- Altitude Intercept Plotting Method

- Determination of Compass Error
- Azimuth using H.O. 229 Sight Reduction Tables (sun and star)
- Amplitude – Celestial Horizon
- Amplitude – Visible Horizon

- Identification of Stars and Planets
- Star Selection

#### Laboratory

- Intro
- Sextant Altitude Corrections
- Coordinate System
- Nautical Astronomy, Navigation Triangle
- Arc to time – Getting Fluid with Time.
- Nautical Almanac - Sunrise, Sunset, Twilight
- Time of LAN
- Latitude of LAN
- Azimuth for Compass Error
- Sight Reduction - Full Sight Reduction SUN
- Sight Reduction - Full Sight Reduction Stars and Planets
- Altitude Intercept Plotting – Running Fix of the Sun and LAN
- Altitude Intercept Plotting - Running Fix of Any Body
- Latitude by Polaris & Azimuth of Polaris

**Other objectives**

The objective of this course is to introduce and familiarize the student with the necessary knowledge of celestial navigation so as to satisfy the STCW Code Table A-II/1 in the following areas:

- Ability to use celestial navigation in times of need, as second check and as a backup navigational system.
- Demonstrate advanced understanding and knowledge of the principles of celestial navigation
- Demonstrate ability to utilize observations of celestial bodies to fix the vessel’s position.
- Demonstrate an ability to utilize observations of celestial bodies to determine error of the compasses
- Demonstrate ability to obtain detailed information from appropriate navigational publications
- Knowledge and ability to successfully complete the USCG Third Mate’s License Exam