This geography lesson is designed for 6 to 12-year-old children to teach them why Earth’s axis is tilted.
Why is the Earth’s Axis Tilted?
The reason for Earth’s axial tilt is not entirely understood, but it is believed to be the result of collisions with other celestial bodies early in the solar system’s history.
Some theories, such as the Giant Impact Hypothesis, describe what happened around 4.5 billion years ago. At the time of the formation of the solar system, all the early forming planets were bombarded with stray material. An asteroid-sized like Mars struck the young earth when it was still forming. In the aftermath, this is how the moon formed and the earth got its axial tilt.
Others propose that gravitational interactions with other planets in the solar system could have caused the tilt. Regardless of its origins, the axial tilt has played a crucial role in shaping the Earth’s environment and climate over time.
What is an Axial Tilt?
In astronomy, the Earth’s axis refers to the imaginary straight line passing from the North Pole to the South Pole on which the Earth rotates.
Whereas the earth’s orbital axis is the line perpendicular to the imaginary plane through which the earth moves as it rotates around the sun.
The earth’s axis tilt is the angle between the earth’s rotational axis and its orbital axis, which is a line perpendicular to its orbital plane. It is also called axial tilt or obliquity.
Over 41000 years, the earth’s obliquity oscillates between 22.1 and 24.5 degrees. Currently, the earth’s obliquity is about 23.4% which results in the changing of the seasons throughout the year.
Since the earth’s axis also wobbles, its obliquity angle also changes. This wobble motion is called axial precession, or the precession of the equinoxes, and is caused by the gravitational force of the Sun, the Moon, and other planets.
Earth’s Obliquity or Axial Tilt Causes Seasons
The axial tilt has a significant impact on the Earth’s climate and weather patterns. As the Earth orbits around the sun, the tilt causes different parts of the planet to receive varying amounts of sunlight, creating seasonal changes. This tilt also affects the intensity of sunlight reaching different parts of the planet, which can lead to differences in temperature and weather patterns.
As a result, we have different seasons and the seasons are opposite in the north and south hemispheres. This video will give a glimpse of the solstices which occur twice annually.
The video lesson teaches the child how the planet earth revolves around the sun and what causes the length of the day and night to vary.
Changes in the Earth’s axial tilt can also have long-term effects on our planet’s climate. For example, changes in the tilt are believed to have contributed to the onset of ice ages throughout Earth’s history.
It is also, important to note that the Earth’s axial tilt is not constant over long periods of time. In fact, it oscillates between 22.1 and 24.5 degrees over a period of about 41,000 years. These changes in axial tilt can have significant impacts on the Earth’s climate and weather patterns over long periods of time.
Watch the video to learn about the earth’s axis tilt using a practical illustration.
Related Video Lessons:
To watch more Montessori science lessons, click here.
Video Created by: Justine McNeilly.
FAQs
- What is Earth’s axial tilt?
Earth’s axial tilt refers to the angle between the Earth’s rotational axis and its orbital plane around the sun.
- What is the current axial tilt of Earth?
The current axial tilt of Earth is approximately 23.5 degrees.
- How does Earth’s axial tilt affect the seasons?
Earth’s axial tilt causes different parts of the planet to receive varying amounts of sunlight, creating seasonal changes.
- What impact does Earth’s axial tilt have on climate and weather patterns?
Earth’s axial tilt affects the intensity of sunlight reaching different parts of the planet, which can lead to differences in temperature and weather patterns.
Tags
- elementary level
- English
- Geography
- science
