Earth Habitability Quiz: Why Nutrients Matter

Study Notes

Geocentric and Heliocentric Models

The geocentric model states that the Earth is the center of the solar system.
The heliocentric model states that the Sun is the center of the solar system.

Earth's Motion

Rotation is the movement of the Earth on its axis, with a period of 24 hours.
The axis is an imaginary line that runs through the center of the Earth, tilted by 23.5 degrees.

Effects of Earth's Rotation

Rotation causes day and night, and affects the flow of air and water on Earth.
The daily rising and setting of the Sun, Moon, and stars are visible patterns in the sky.

Revolution

Revolution is the movement of the Earth around the Sun in its orbit, taking 365.25 days to complete.
Perihelion is the point when the Earth is closest to the Sun, at a distance of 147.1 million kilometers.
Aphelion is the point when the Earth is farthest from the Sun, at a distance of 152.1 million kilometers.

Effects of Earth's Revolution

The different regions of the Earth experience varying amounts of sunlight throughout the year.
Revolution causes seasonal changes, resulting from the changing amount of solar radiation an area receives.

Seasons

In June, July, and August, the Northern Hemisphere faces the Sun, while the Southern Hemisphere faces away.
In September, October, and November, the axis of the Northern and Southern Hemispheres move sideways, receiving less energy from the Sun.
In December, January, and February, the North Pole faces away from the Sun.
In March, April, and May, the Northern Hemisphere experiences spring.

Factors for a Habitable Planet

Temperature: influences the speed of molecular movement, with a range of -15°C to 115°C suitable for life.
Atmosphere: traps heat, shields the surface from radiation, and provides chemicals needed for life.
Nutrients: necessary for growth, with a system to deliver them to organisms (e.g., water cycle or volcanic activity).
Energy: necessary for life processes, with a steady input of light or chemical energy.
Water: dissolves and transports chemicals within and to cells, with regular availability.

Characteristics of Habitable Planet Earth

Right distance from the Sun
Protected from harmful solar radiation by its magnetic field
Kept warm by an insulating atmosphere
Right amount of ingredients for life

Description

Test your knowledge on the unique characteristics of planet Earth that set it apart from other planets in the solar system. Learn about the geocentric model, heliocentric model, Earth's motion including rotation and revolution, and the concept of Earth's axis tilt.