TOPIC 8 A (F) OBJECTIVES
THE EARTH IN SPACE
1. Determine the characteristics that allow for life to exist on planet Earth.
The Earth has the right temperature to support a large variety of life. This is a result of the Earth's distance from the Sun, atmosphere and oceans. Earth also has liquid water.
2. a. Define rotation.
When an object spins on its own axis.
b. Define revolution.
When one object travels around another.
3. Explain how the Foucault's pendulum and the Coriolis effect demonstrate that the Earth rotates.
If the Earth did not rotate a large pendulum would continually travel over the same spots on the floor. However, because the Earth does rotate the pendulum travels over different spots on the floor. The Coriolis effect causes winds to curve as a result of the rotation of the Earth. If the Earth did not rotate most winds would only travel north and south.
4. Identify the path of the Sun, as viewed in the United States, in the following terms:
1) Location of Sun rise.
The Sun rises in the East, the location changes everyday in a cyclic pattern. Only on the equinoxes is it due east.
2) Location of Sun set.
The Sun sets in the West, the location changes everyday in a cyclic pattern. Only on the equinoxes is it due west.
3) Height of arc at noon.
The altitude of the Sun at solar noon also changes daily in a cyclic pattern. The Sun is never at 90o.
5. Describe and identify from diagrams, the Sun's daily path through the sky for all four seasons in New York State.
The students have a worksheet, which has a diagram showing the path of the Sun as seen in New York at different times during the year.
6. List two factors that determine the apparent path of the Sun.
1) The date, in the same location the apparent path of the Sun changes on a daily bases.
2) The location, on the same day the Sun's apparent path changes as a person's latitude changes.
7 a. Explain how the angle of the sun varies on a daily cycle.
At Sun rise the altitude of the Sun is 0o. The altitude increases until solar noon then decreases until Sun set.
b. Explain how the angle of the sun varies on an annual cycle.
North of the equator the altitude of the Sun at solar noon is at a maximum on June 21. It then decreases until December 21.
8. Identify the southern and most northern latitudes at which the sun can be seen directly overhead at some point during the year.
Southern: 23 1/2o S, which is called the Tropic of Capricorn
Northern: 23 1/2o N, which is called the Tropic of Cancer
9. Compare the location of the noon Sun and length of day from other latitudes with positions in New York State.
The closer a location is the equator the more stable the hours of daylight is. As you move towards the poles the range in daylight hours increases. To have the Sun at the zenith at solar noon your location must be between 23 1/2o N and 23 1/2o S.
10. Examine the patterns of the length of the day at the equator and the poles.
At the equator the length of day is very constant, 12 hours. At the poles the length of day varies from 0 hours to 24 hours.
11. Identify the relationship between the length of daylight hours and the temperature of a location.
As the duration of insolation increases the temperature increases.
12. List the factors, which cause the seasons.
The three factors that cause seasons are that the Earth revolves around the Sun, as the Earth revolves around the Sun its axis is tipped, and finally the axis tip always points to the same spot in space.
13. Identify the location of each of the four seasons in a diagram of Earth's orbit.
The students have a diagram with this information on it.
14 a. Explain the cause of the phases of the Moon.
The Moon is visible only because it reflects light from the Sun. The appearance of the reflected light changes because the Moon revolves around the Earth.
b. On a diagram or model of the Earth, Sun, and Moon system, identify the eight phases of the Moon.
The students have this information on a diagram.
c. Identify the length of time required for the Moon to go through one cycle of phases.
It takes the Moon 29.5 days to go through one cycle of lunar phases.
15 a. Identify the cause of the tides.
Tides are caused by the gravitational attraction of the Moon and Sun which cause a bulge in the ocean to form. When the Earth rotates into the bulge it causes high tide.
b. Construct or interpret graph of tide data.
The student's have a worksheet, which covers the graphing of tides.
16 a. Identify the causes of solar and lunar eclipses.
Solar eclipses are caused when the Moon blocks our view of the Sun.
Lunar eclipses are caused when the Earth's shadow covers the Moon.
b. Explain why we don't experience solar and lunar eclipses each month.
The Moon's orbital plane around the Earth is not the same as the Earth's orbital plane around the Sun.
