Lab#8: Sun’s Path across the Celestial sphere for various Latitude during different seasons

Seasons Interactive (128.0K)
That our seasons come from the tilt of Earth’s axis relative to its orbit of the Sun is easy to grasp, once you have used this Interactive. It shows the flow of seasons as the planet orbits the Sun, the angle of the Sun’s rays for a given location on Earth, how temperature varies at that location, and how the Sun’s path varies in the sky by season. Choose from 3 planets to see how their seasons reflect their unique tilts, or customize the tilt. What would “winter” be like if Earth had no tilt? This Interactive will show you.

Popular Astronomy Misconceptions

As basic as it all sounds many people, many smart people, really don't understand the motion of the Earth, Sun and Moon and how it affects how we experience our world. They believe they understand simple facts about celestial motion but instead they often subscribe to a number of very common or popular misconceptions. Take, for example, the following questions and answers about two basics of celestial motion:

Question #1: What causes the seasons? Answer: The seasons are caused by the Earth's changing distance from the Sun. When the Earth is closer to the Sun it grows warmer so we have summer. When the Earth is farther from the Sun it is less warm so we have winter.

Get the answers by going to this website http://people.bu.edu/sscruggs/index.html

for the lab you may read http://people.bu.edu/sscruggs/earthandsunhome.html

Conclusion questions:

1.      

1. On which day does the sun have its highest altitude at noon for the Northern Hemisphere? Do you expect cooler or warmer air temperature in this day? State the relationship between the tilt of the earth’s axis at the North Pole and the sun’s rays; whether the North Pole is tilted toward the Sun, away from the sun or perpendicular to the Sun's rays. Use the diagrams in the introduction to explain why this is possible.

2.       On which day does the sun have its lowest altitude at noon for the Northern Hemisphere? Do you expect cooler or warmer air temperature in this day? State the relationship between the tilt of the earth’s axis at the North Pole and the sun’s rays; whether the North Pole is tilted toward the Sun, away from the sun or perpendicular to the Sun's rays. Use the diagrams in the introduction to explain why this is possible.

3.       On which day does the earth receive the greatest amount of daylight in the Northern Hemisphere? State the relationship between the tilt of the earth’s axis at the North Pole and the sun’s rays; whether the North Pole is tilted toward the Sun, away from the sun or perpendicular to the Sun's rays.? Do you expect cooler or warmer air temperature in this day? Use the diagrams in the introduction to explain why this is possible.

4.  On which day does the earth receive the least amount of daylight in the Northern Hemisphere? State the relationship between the tilt of the earth’s axis at the North Pole and the sun’s rays; whether the North Pole is tilted toward the Sun, away from the sun or perpendicular to the Sun's rays. Do you expect cooler or warmer air temperature in this day? Use the diagrams in the introduction to explain why this is possible.

5.       What is the relationship between the tilt of the earth’s rotational axis, the altitude of the sun at noon and the amount of daylight hours the Earth receives and expected air temperature (cooler or warmer)?

6.       How many days in New York is the Sun directly overhead (at the observer’s zenith)?

7.       Which latitude receives the Sun directly overhead (at the observer’s zenith) two times per year?

8.       What is the relationship between the lengths of Sun’s paths (day time hours) for the same dates in Northern and Southern Hemispheres?