What causes day and night?
An Educator’s Reference Desk Lesson Plan Submitted by: Karen Machak Email: machak4@aol.com School/University/Affiliation: University of Pittsburgh – Johnstown Endorsed by: B. Poole – University of Pittsburgh – Johnstown Date: January 30, 2000 Grade Level(s): 5, 6 Subject(s): • Computer Science Duration: 45 minutes Description: A simple experiment investigating what causes day and night. Students graph the hours of night and day from sunrise and sunset times found on the Internet. Goals: Students will gain an understanding of the earth’s relationship to the sun. Objectives: Students will be able to demonstrate day and night on earth, and chart the number of hours of light and darkness for one year. Materials: • flashlights • balls • graph paper • crayons • globe Procedure: Computer Integration: One computer in the classroom: The teacher can print out the sunrise and sunset times ahead of time and then in class show the students where to find the information. Limited number of computers
The axis of the Earth is an imaginary line that passes through the North and the South poles. The Earth takes approximately twenty-four hours to complete one rotation. The Sun is the source of light. At the time of the rotation, it is day on the side of Earth that faces the Sun; while it is night on the other side of Earth not facing the Sun. The position of the Sun is fixed and it does not change. The Sun rises in the east because the Earth is moving towards the east. Later, in the mid noon the Sun is in the south because Earth is moving towards the south and gradually towards the west and the Sun sets. The length of the day is measured from the time the Sun rises to the time the Sun sets. Another interesting fact about Earth is that because Earth tilts on its axis, it is day in the southern hemisphere and night in the northern hemisphere and vice versa. The axis of the Earth is always tilted at an angle of 23.5 degrees. The rotation of the Earth on its own axis not only results in da
