Science project idea on seasons.
Seasons Science Project Idea
Since light and heat come from the sun, the difference between winter and summer must be in some way associated with some difference in relation between the sun and the earth. Likewise our calculation of time must be based on the relation between the earth and the sun. Every morning we see the sun rise in the east and at the end of the day set again in the west. Science Project Idea on Why we have winter and summer There are several facts with which we are familiar that will help us to understand the cause of the seasons. What is the comparative length of day and night during winter and summer? What is the relative height of the sun above the horizon at midday in winter and in summer? Evidently the sun shines more directly upon our part of the earth in summer than in winter. We have already learned that the earth rotates (turns) upon its own axis, and revolves around the sun. If the axis of the earth is at right angles to an  imaginary line running from the earth to the sun, what part of the earth would always receive the most direct rays of the sun? But since during the summer the portion of the earth north of the equator receives the most direct rays of the sun, and during the winter the same region receives fewer direct rays of the sun, what is your conclusion in regard to the direction of the earth's axis?
Since on our longest day in summer the direct rays of the sun strike a point 23 degrees north of the equator and on the shortest day of our winter strike a point 23 degrees south of the equator, we know that the axis of the earth is inclined 23 degrees to the imaginary line running from the earth to the sun. A careful study of the following figure will make clear how the revolution of the earth and the inclination of its axis cause the seasons.  1. At what times in the year are the days and nights equal in length? These times are called the vernal or spring equinox, and the autumnal or fall equinox.
2. On June 22, 1919, at New York City, the sun rose at 4:28 A.M. and set at 7:35 P.M. What was the length of the period of daylight? What was the length of the daylight period within the arctic circle (23 degrees from the north pole) on this date? 3. In your own language discuss the changes in the length of day and night starting with June 22, as the earth revolves around the sun.
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