Celestial Navigation (CEL)

• DGS EXAMINATION FORMAT

• Introduction

• Solar System

• Celestial Poles

• Perihelion and Aphelion

• Kepler's Laws of Planetary Motion

• Solstices and Equinoxes

• SHA

• Declination of Bodies

• d', 'v' Corrections

• Twilight

• Earth - Moon System

• Solar and Lunar Eclipses

• Celestial Sphere and Equinoctial System of Co-ordinates

• Celestial Sphere, Celestial Poles and Celestial Meridians

• Equinoctial

• Obliquity of Ecliptic

• Hour Angle

• GHA, LHA and SHA

• Right Ascension

• Daily Motion and Horizon System of Co-ordinates

• Rational Horizon, Zenith, Nadir and Vertical Circle

• Projection of PZX Celestial Spherical Triangle on the Plane of Rational Horizon

• Elevated Pole and Depressed Pole

• True Altitude, Azimuth and True Zenith Distance

• PZX Triangle and Circumpolar Bodies

• Sextant and Altitude Corrections

• Errors of Sextant

• Reading a Sextant

• Index Error

• Visible, Sensible and Rational Horizons

• Observed Altitude, Dip, Apparent Altitude

• Calculation of True Amplitude

• Refraction, Semi-Diameter, and Parallax

• Amplitude

• Theoretical and Visible Sunrise and Sunset

• Time

• Relationship Between LHA (Sun) and LAT

• Equation of Time and Solar day

• GMT, LMT and Longitude Relationship

• Zone and Standard Times

• Nautical Almanac-Information in Nautical Almanac and using it for Celestial Observations

• Latitude by Meridian Altitude-Calculation of Latitude by Meridian Altitude

• Pole Star Observations

• Identification of Polaris, a0, a1, a2 Corrections

• Calculation of Azimuth and Position Line and a Position Through Which it Passes

• Position Fixing

• Ex-Meridian of Sun

• Long by Chron and Intercept Methods of Sight Calculation

• True Azimuth of a Body

• Position Finding by Simultaneous and Staggered Observations

• Fixing Out of Sight of Land

• Errors of Compasses - Azimuths

• Calculation of Magnetic Compass and Gyro Compass Errors by Observing Heavenly Bodies

• Calculation of Magnetic Compass and Gyro Compass Errors by using ABC Tables