Download 43 Astronomy 43.1 Recall that Earth is one of the many planets in

4­3 Astronomy 4­3.1 Recall that Earth is one of the many planets in the solar system that orbit the Sun. Essential Question: What is in our solar system? Textbook Pages: 208­209 Sun ● central star in our solar system ● all planets in our solar system orbit around the Sun Planets ● bodies (natural satellites) that orbit the Sun (a star) ● 8 planets in our solar system in order from the Sun: o Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, (Pluto­ Dwarf Planet) Essential Question: How are the planets in or solar system alike and different? Textbook Pages: 212­215 Rocky Planets (Smallest Planets) ● Earth, Mercury, Venus, Mars Gas Giants (Largest Planets) ● Jupiter, Saturn, Neptune, Uranus Why is Earth unique? ● It is the only planet with life. 4­3.2 Compare the properties (including the type of surface and atmosphere) and the location of Earth to the Sun, which is a star, and the Moon. Essential Question: How do the Sun, Earth, and Moon compare? Textbook Pages: 190, 213, 196­197 Sun ● a star, a large ball of glowing gases that is extremely hot ● does not have a rocky surface and its atmosphere glows and gives off light ● located at the center of the solar system ● Earth and other planets revolve around it Earth ● rocky surface and has water on it ● atmosphere of gas around it ● orbits millions of miles from the Sun as the third planet in the solar system Moon ● natural satellite that orbits the Earth ● rocky, dusty surface with many craters and no water ● no atmosphere 4­3.3 Explain how the Sun affects Earth. Essential Question: How does the Sun affect Earth? Textbook Pages: 188­190 The Sun’s energy… ­travels through space before Earth receives it ­provides Earth with heat and light ­cause weather conditions and evaporation ­is stored in fossil fuels (coal, oil, natural gas) that formed from organisms that died long ago ­is used by plants to make food The Sun provides almost all of the light and heat energy that Earth must have to survive. 4­3.4 Explain the tilt of Earth’s axis and the revolution around the Sun results in the seasons of the year. Essential Question: How does the tilt of the Earth’s axis and the revolution around the Sun result in the seasons? Textbook Pages: 184­187 The Earth has seasons because Earth’s axis is tilted and Earth revolves around the Sun. ● Because of the tilt, the number of daylight hours change throughout the year ● As Earth revolves around the Sun, different parts of Earth get more sunlight ● The two hemispheres have opposite seasons ● The seasons do NOT depend on the distance of Earth from the Sun Axis­ an imaginary line that Earth rotates on; runs through the planet’s center Revolution­ the movement of Earth as it makes an orbit around the Sun in one year ● Earth revolves around the Sun one time each year in about 365 days Seasons­ effects on Earth due to the change in the amount of sunlight caused by the tilt of Earth’s axis ● When Earth tilts towards the Sun, the season is summer ● When Earth tilts away from the Sun, the season is winter ● Autumn/Fall and spring occur when neither part of Earth is tilted directly towards or away from the Sun ● Sequence of the seasons: Summer, Autumn/Fall, Winter, Spring 4­3.5 Explain how the rotation of Earth results in day and night. Essential Question: How does the rotation of the Earth result in day and night? The rotation of the Earth causes day and night ● Earth rotates (spins) on an axis and completes one rotation ion 24 hours ● Earth rotates from west to east; therefore, the Sun rises in the east and sets in the west ● The side of Earth facing the Sun is lit and experiences day; The side of Earth facing away from the Sun experiences night 4­3.6 Illustrate the phases of the Moon and the Moon’s effect on ocean tides. Essential Question: How does the Moon affect the Earth? Textbook Pages: 200­201 Ocean Tides ● Gravity causes the Earth and the Moon to pull on each other ● The Moon’s pull on Earth makes the level of the ocean rise and fall. This change in level is called tide. o There are two high tides and two low tides each day o High tide: ocean water level is the highest o Low tides: ocean water level is the lowest; occur between high tides Essential Question: How does the Moon affect the Earth? Textbook Pages: 198­199 Phases of the Moon The Moon reflects light from the Sun, and just like Earth, half of the Moon is always lit by the Sun. Because of the positions of the Sun, the Moon and Earth, the Moon appears to change shape. The amount of ​
reflected​
light from the Moon that is seen from Earth determines the phase. The changing shapes of the Moon are called phases​
. There are four main phases: ● New Moon­ the entire half/side of the Moon facing Earth is ​
dark​
. ● Quarter Moon­ half of the side of the Moon facing Earth is ​
light​
and the other half is ​
dark​
; the Moon appears as a ​
half​
circle; there are two quarter Moon phases in the cycle. Can also be called Half Moon. ● Full Moon­ the entire half/side of the Moon facing Earth is ​
lighted​
; the Moon appears as a full ​
circle​
. ● Crescent Moon­ a small section (less than a quarter moon) of the half/side of the Moon facing Earth is lighted. 4­3.7 Interpret the change in the length of shadows during the day in relation to the position of the Sun in the sky. Essential Question: How does the height of the Sun in the sky affect shadows? Textbook Pages: 184­185 Objects on Earth cast shadows that help show Earth’s rotation. The angle of the Sun changes the length of an object’s shadow. ● In the morning, the Sun appears low in the sky; objects cast long shadows ● As Earth rotates, the Sun appears higher in the sky, and the shadows get shorter ● At noon, with the Sun overhead, objects cast short shadows or no shadow at all ● As Earth continues to rotate and the Sun appears lower in the sky toward evening, the shadows get longer again 4­3.8 Recognize the purpose of telescopes. Essential Question: What is the purpose of a telescope? Textbook Pages: 210­211 Telescopes are tools that aid in the study of objects in outer space. ● Can gather more light than the eye, so it makes faint, faraway objects seem brighter and closer.