Celestial Navigation I

Capt. Bernabe LimINSTRUCTOR

Perihelion and

Aphelion

PERIHELION

•closest point of Earth to sun•distance about 1.5 M miles less than the mean distance•occurs on early January

APHELION

•Farthest point to sun•about 1.5 M miles greater than the mean distance•occurs on early July

MOTION OF BODIES OF THE SOLAR SYSTEM

• Video

Two principal motions• Rotation• Revolution

ROTATION

ROTATION

• Rotation of Earth around axis• Rotates to East• Turns counter-clockwise• Daytime and night time• 24 hours or 1 day

REVOLUTION

•Motion of body in elliptical orbit•365.25 days or a year

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