Name ______MET 102 Sun’s Apparent Path

The diagram below represents a model of the sky as seen from a location in the Northern Hemisphere. Two external protractors have been placed along the north-south line so that altitude above the north horizon and south horizon can be determined.

Diagram A

Directions for Diagram A:

1. Diagram A represents the sky as seen from a latitude of 50 degrees North. 2. On the dome, draw in Polaris at its correct altitude. 3. On the dome, label the correct location of the zenith. 4. Draw an arrow to the horizon and lightly shade in the portion of the diagram that represents Earth’s surface. 5. Label the positions of east, west, and south on the diagram. 6. What is the altitude of the celestial equator above the southern horizon? ______7. Draw an arc representing the position of the celestial equator on the sky. Remember that it is an arc that goes from due east to due west across the sky. 8. The sun’s path for the winter solstice: a. What is the sun’s declination on the winter solstice? ______b. Based on your answer to 8a, determine the altitude of the sun at solar noon on the winter solstice. ______c. What is the date of the Northern Hemisphere’s winter solstice? ______d. Draw a circle on the model representing the sun at solar noon on the winter solstice. Label the position of the sun at solar noon on the winter solstice using WS Noon. e. Draw an arc representing the sun’s apparent path on the winter solstice. i. Draw arrows along the arc representing the apparent direction the sun appears to move across the sky. ii. Draw an arrow to the position of sunrise and label it SR. iii. Draw an arrow to the position of sunset and label it SS.

MET 102 Professor Vorwald Page 1 of 3 9. The sun’s path for the summer solstice: a. What is the sun’s declination on the summer solstice? ______b. Base on your answer to 7a, determine the altitude of the sun at solar noon on the summer solstice. ______c. What is the date of the Northern Hemisphere’s summer solstice? ______d. Draw a circle on the model representing the sun at solar noon on the summer solstice. Label the position of the sun at solar noon on the summer solstice using SS Noon e. Draw an arc representing the sun’s apparent path on the solstice. i. Draw arrows along the arc representing the apparent direction the sun the sun appears to move across the sky. ii. Draw an arrow to the position of sunrise and label it SR. iii. Draw an arrow to the position of sunset and label it SS. 10. The sun’s path for the spring equinox: a. What is the sun’s declination on the spring equinox? ______b. Base on your answer to 10a, determine the altitude of the sun at solar noon on the spring equinox. ______c. What is the date of the Northern Hemisphere’s spring equinox? ______d. Draw a circle on the model representing the sun at solar noon on the spring equinox.. Label the position of the sun at solar noon on the spring equinox using SPE Noon e. Draw an arc representing the sun’s apparent path on the spring equinox. i. Draw arrows along the arc representing the apparent direction the sun appears to move across the sky. ii. Draw an arrow to the position of sunrise and label it SR. iii. Draw an arrow to the position of sunset and label it SS.

11. If you were to draw in the sun’s path for the Northern Hemisphere’s fall equinox, where would you draw the arc? ______

12. What real Earth motion is the cause of the apparent daily path of the sun across the sky?

______

13. What is the inclination of Earth’s rotational axis to a line perpendicular to the plane of it’s orbit?

______

14. How do the changes in the yearly path of the sun throughout the year provide the information necessary to determine the inclination of Earth’s axis?

______

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MET 102 Professor Vorwald Page 2 of 3 Diagram B

Directions for Diagram B:

1. Diagram B represents the sky as seen from a latitude of 30 degrees North. 2. On the dome, draw in Polaris at its correct altitude. 3. On the dome, label the correct location of the zenith. 4. Draw an arrow to the horizon and lightly shade in the portion of the diagram that represents Earth’s surface. 5. Label the positions of east, west, and south on the diagram. 6. What is the altitude of the celestial equator above the southern horizon? ______7. Draw an arc representing the position of the celestial equator on the sky. Remember that it is an arc that goes from due east to due west across the sky. 8. The sun’s path for the winter solstice: a. What is the sun’s declination on the winter solstice? ______b. Based on your answer to 8a, determine the altitude of the sun at solar noon on the winter solstice. ______c. What is the date of the Northern Hemisphere’s winter solstice? ______d. Draw a circle on the model representing the sun at solar noon on the winter solstice. Label this winter solstice solar noon. e. Draw an arc representing the sun’s apparent path on the winter solstice. i. Draw arrows along the arc representing the apparent direction the sun appears to move across the sky. ii. Draw an arrow to the position of sunrise and label it SR. iii. Draw an arrow to the position of sunset and label it SS. 9. Compared to a latitude of 50 degrees north, the number of hours of daylight at 30 degrees north on the winter solstice is (circle your choice) a. Lower b. Greater c. The same

MET 102 Professor Vorwald Page 3 of 3