Question

earth - sun models
earth has a nearly circular orbit around the sun. earth also rotates around its north - south axis, an imaginary line passing through earth from pole to pole.

1. examine the image. what does this model show? circle all that apply.

a. every place on the planet gets 12 hours of light and 12 hours of dark each day.
b. temperature conditions on the planet change depending on distance from the sun.
c. there are colder temperatures at the poles and warmer temperatures at the equator, but no temperature changes during the year.

1. does this first model explain the seasons that happen on earth? give at least one example to support your answer.

unlike the planet in the first model, earths axis is not perpendicular to the plane of earths orbit around the sun. earths axis is tilted 23.5° from perpendicular to the plane of its orbit. this tilt remains the same throughout earths orbit. earths axis is pointed in the same direction no matter where earth is in its orbit around the sun.

Explanation:

21

A

The model shows that the Earth's axis is not tilted. In reality, only during the equinoxes do most places get approximately 12 hours of light and 12 hours of dark. But in this model (axis - not tilted), every place on the planet would get 12 hours of light and 12 hours of dark each day.

B

The Earth has a nearly circular orbit around the Sun. The distance from the Sun does not change enough in this model to cause significant temperature changes. Temperature conditions on the planet do not change depending on distance from the sun in this model.

C

Since the axis is not tilted, the angle at which sunlight hits different parts of the Earth (poles and equator) remains the same throughout the "year" (orbit). So, there are colder temperatures at the poles (because sunlight is more spread out) and warmer temperatures at the equator (because sunlight is more concentrated), but no temperature changes during the year.

22

The first model does not explain the seasons on Earth. Seasons on Earth are caused by the tilt of the Earth's axis. For example, in the Northern Hemisphere, when the Earth's axis is tilted towards the Sun, it is summer (more direct sunlight). When it is tilted away, it is winter. In the first model (axis - not tilted), there would be no such variation in sunlight intensity throughout the orbit, so no seasons as we know them on Earth.

Answer:

1. A. Every place on the planet gets 12 hours of light and 12 hours of dark each day; C. There are colder temperatures at the poles and warmer temperatures at the equator, but no temperature changes during the year.
2. No. Seasons on Earth are due to the tilt of the Earth's axis. In the first model (axis - not tilted), there is no variation in sunlight intensity throughout the orbit to cause seasons like the summer - winter cycle in the Northern and Southern Hemispheres.