Here is the notes from Class 6 NCERT Geography – Chapter 3: Motions of the Earth

Two Types of Motions of the Earth

• Rotation

• • Definition: Movement of Earth on its axis.
  • Direction: From west to east.
  • Time Taken: 24 hours (1 day).
  • Effect: Causes day and night.
  • Axis: An imaginary line passing through the North and South Poles.
  • The Earth’s axis is tilted at 66½° from its orbital plane.

• Revolution

• • Definition: Movement of the Earth around the Sun.
  • Path: Elliptical orbit (oval-shaped).
  • Time Taken: 365¼ days (1 year).
  • To adjust the extra ¼ day → Leap Year every 4 years (with 366 days).

• Circle of Illumination: The circle that divides the day from night on the globe

• Earthday: The earth takes about 24 hours to complete one rotation around its axis, and period is known as Earthday.

•  Seasons is caused by

• • • • Tilt of Earth’s axis
      • Revolution around the Sun

  • Four main seasons:

    • Summer
    • Winter
    • Spring
    • Autumn

Important Days Related to Seasons

• Summer Solstice – 21st June

  • Northern Hemisphere tilts towards the Sun.
  • Longest day and shortest night in the Northern Hemisphere.
  • It is summer in Northern, and winter in the Southern Hemisphere.

•  Winter Solstice – 22nd December

  • Southern Hemisphere tilts towards the Sun.
  • Longest day and shortest night in the Southern Hemisphere.
  • It is winter in the Northern, and Summer in Southern Hemisphere

•  Spring Equinox – 21st March

  • Equal day and night all over the world.
  • Sun is directly above the Equator.
  • It is Spring in Northern, and Autumn in Southern Hemisphere

•  Autumn Equinox – 23rd September

  • Equal day and night all over the world.
  • Sun is directly above the Equator.
  • It is Autumn in Northern, and Spring in Southern Hemisphere