Ecliptic

11.11 - Know that most bodies in the Solar System orbit the Sun in, or close to, a plane called the ecliptic

5.2 - Understand the observed motion of the Sun follows an annual path called the ecliptic

5.4 - Understand the observed motion of the planets takes place within a narrow Zodiacal Band

5.6 - Understand the terms First Point of Aries and First Point of Libra

Planets and most bodies follow orbits around the Sun. The +path they follow is called the ecliptic. This is an imaginary line (or plane) between the Sun and the Earth. The Sun appears to follow this line in the sky throughout the year on a line that crosses 13 constellations. In fact it is the Earth moving around it. These constellations are known as the zodiac.

Not all planets follow this line exactly, they usually move a degree or two either side. This is called their inclination.

Earth's axis is not in line with the ecliptic. It is titled at an angle of approximately 23.5°.

Notable exeptions to bodies that move near the ecliptic are the majority of comets and dwarf planets.

 

Questions
  • Describe the ecliptic.
  • Terms: Many people get confused between ecliptic and elliptic. What is the difference between them?
  • What is the zodiac?
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