1. Activating Strategy
Describe how objects seem to move across the sky [What can you observe?]. Why do objects seem to move across the sky? When instructed, share your response with another student.
Instructional Approach(s): The teacher should give students about 30 seconds to think on their own and then allow them to discuss the questions with another student. Although the questions seem simple, the students may not have an answer for why it occurs. After a minute or less of allowing students to discuss the questions, bring the class back together and tell them this is exactly what they will be discussing in the lesson.

2. Essential Question: Why do objects seem to move across the sky?
Standard S6E1d. Explain the motion of objects in the day/night sky in terms of relative position.
Instructional Approach(s): The teacher should introduce the essential question and the standard aligned to the essential question.

3. Use your notes to record important information.

4. Movement of Objects in the Sky
The sun, the stars, the moon and other planets all appear to move across the sky.
In which direction do they seem to move?
The sun, the stars, the moon and other planets appear to rise in the East and set in the West.
But why?
Instructional Approach(s): The teacher should present the first statement to the class while the students answer the first question on their notes. Ask the class, in which direction do they (the objects) seem to move? Once one or two students have responded, click for the next statement and have students record the information on their notes. Lastly, ask the students why object seem to move across the sky in this direction. After a few responses from students, move to the next slide describing why objects move across the sky.

5. All the motions and changes you see are a result of 4 simple facts:
The Earth is spinning on its axis [one turn every 24 hours].
2. The Moon is orbiting around the Earth [one orbit every 27.3 days].
Instructional Approach(s): The teacher should present the information to the students while they record the important information on their notes.

6. All the motions and changes you see are a result of 4 simple facts:
The Earth and all the other planets are orbiting the Sun, all in the same direction, and all in roughly the same plane (i.e. it's like they are all laid out on a large dinner plate with the Sun at the center). The outer planets orbit more slowly than the inner planets.
4. The stars appear stationary. (They do, in fact, move very quickly. But they are so far away that the motion appears to us to be too slow to perceive without special instruments.)
Instructional Approach(s): The teacher should present the information to the students while they record the important information on their notes.

7. Standing on the ground, we do not perceive the motion of the Earth, its rotation or its orbit around the Sun -- instead, it seems to us as though we are stationary and the sky is moving around us.
Instructional Approach(s): The teacher should present the information on the slide.

8. Here is an example of how the rotation of the Earth makes the Sun appear to move across the sky: If an object is at a fixed location on a wall (for example, a clock) and you are facing it, then you can see the clock. If you rotate so that you’re facing away from the clock, you can no longer see it. While you are rotating, the clock will, from your point of view, appear to be moving.
Instructional Approach(s): The teacher should present the information on the slide. If possible, have students stand up and demonstrate the process.

9. Like the sun, if you pick out a star in the sky, it will appear to make an arc across the sky. This is because, for our purposes, we can consider the star to be fixed in space, and the Earth is rotating underneath it.
Instructional Approach(s): The teacher should present the information on the slide.

10. It happens slowly. From minute to minute you do not notice the star's motion.
However, over the course of a few hours you will be able to tell that the stars have moved a substantial distance in the sky.
Like the Sun, the stars will (for the most part) appear to rise in the east and set in the west.
Instructional Approach(s): The teacher should present the information on the slide.
The images to the right are time exposure photos taken of the same stars over the same spot.

11. Think of how you would see stars during the earth’s rotation using the diagram below.
Instructional Approach(s): The teacher should use the diagram to help illustrate the concept .

12. When the Sun appears during the day in the Summer, the winter constellations are obscured by the sunlight bathing our atmosphere, and when night falls, the summer constellations are visible. Conversely, the summer constellations are obscured by the Sun during days in Winter, while the winter constellations are visible at night
Instructional Approach(s): The teacher should present the information on the slide.

13. Time lapse videos of stars
Instructional Approach(s): The teacher should show the time lapse videos to reinforce the concepts.

14. The North Star appears to remain stationary in the sky. Why
The North Star appears to remain stationary in the sky. Why? The North Star lies almost perfectly above the Earth's rotational axis
North Star
Instructional Approach(s): The teacher should present the question on the slide and see if students can come up with the answer. After a short period of time, show the answer and have students record the answer on their notes. Use the image to reinforce the concept.

15. Possible Activities
Students can draw a diagram illustrating what causes objects to appear to move across the sky [box on notes for illustration]
Students can make a flipbook illustrating objects seeming to move across the sky (be sure they include the cause of the appeared movement). The following website provides information on making a flipbook:
Modeling the Night Sky [see resource page]
Instructional Approach(s): The teacher can select one of the suggested activities to reinforce the concepts of the lesson or create another aligned activity.

16. Summarizing Strategy: 3-2-1
Identify 3 objects that appear to move across the sky.
Identify 2 interesting facts from today’s lesson.
Identify the main reason objects appear to move across the sky.
Instructional Approach(s): Each student should complete the summarizing strategy. The teacher should read each summarizing response to determine student mastery and differentiation should occur.