AIM: How do interactions among objects in space and their forces affect objects and cause predictable & regular changes on Earth? 5/1/13 DO NOW: Pick up today’s quiz & finish it Put last night homework in the basket. HOMEWORK: Read p. 1-6 in your PS ILS Review Book. Answer Questions #1-33 from p. 7-13 on the scantron. SCANTRON DUE- tomorrow by 8 AM Study for tomorrow’s quiz on PKKI#1 LE ILS Flash Cards DUE-5/6

Identify the objects that make up our solar system. Sun Planets & their moons Asteroids Comets Meteoroids What force holds all of these objects in orbit around the sun? Gravity

What two factors determine the gravitational attraction? A body’s mass Its distance from the object How does mass affect an object’s gravity? The greater the mass of an object, the greater its gravity How does distance from an object affect gravity? The closer an object is to another in space, the more gravity it will experience

ILS Question Which force keeps the planets in their orbits around the Sun? (1) gravity (2) magnetism (3) electricity (4) friction Which body in our solar system is classified as a star? (1) Earth (2) Mars (3) Venus (4) Sun

ILS Question The diagram at right shows a portion of the solar system as seen from space. For which object is the lighted surface shown incorrectly?

ILS Question In the diagram below, the letters A, B, and C represent three identical satellites and their relative distances from Earth as seen from space. Which satellite would experience the strongest pull of Earth’s gravity? State a scientific principle that explains your answer in question 1. Predict what might happen to satellite B if the forces acting on it become unbalanced.

What is rotation? The spinning of the Earth on its axis What is revolution? The movement (orbit) of the Earth around the sun

What causes day/night here on Earth? The rotation of Earth on its axis How long does it take for the Earth to make one rotation on its axis? 24 hours (1 day) How long does it take the Earth to make one complete orbit (revolution) around the sun? 365.25 days (1 year)

What causes seasons on Earth? Tilt of the Earth’s axis The revolution (orbit) of the Earth around the Sun. At which position is the earth experiencing summer in the Northern Hemisphere? A

ILS Question Earth at one point in its orbit around the Sun. The length of daylight experienced at different latitudes on a given date is shown on the diagram. Describe how the length of daylight changes from the Equator to the North Pole on the date shown. What season is beginning in the Northern Hemisphere? Explain why the South Pole receives 24 hours of daylight on the date shown.

ILS Question The diagram below shows Earth, as viewed from space, as it moves around the Sun. Approximately how long does it take Earth to move from position A to position B? The Sun appears to move across the sky during the day. The best explanation for this apparent motion is that Earth is ________.

ILS Question The diagram below shows Earth as seen from space. Letters A through D are locations on Earth’s surface. When Earth is in this position, which location would experience the greatest number of daylight hours?

ILS Question The diagram shows Earth’s revolution around the Sun as viewed from space. Positions A, B, C, and D represent the beginning of each season on Earth. State one reason that Earth has seasons. If Earth were at position D, how much time would it take to return to position D? Which season begins in the Northern Hemisphere when Earth is at position A?

How are we able to see the moon in the night sky? The moon reflects the sun’s light What causes the moon to change phases during the month? The revolution of the moon around the Earth. How long does it take the moon to go from full moon phase to the next full moon phase? 29 days

Which position indicates a full moon phase? Which position indicates a new moon phase? A

ILS Question The diagram shows the position of Earth and four positions of the Moon during one orbit of Earth. On the diagram, draw an X to show where the Sun would need to be located to create the Moon phases shown. Which letter in the diagram shows the position of the Moon when an observer on Earth sees a full Moon? What motion is represented by the arrows in the diagram?

ILS Question Approximately how long does it take to cycle from one new Moon to the next new Moon? (1) a day (2) a week (3) a month (4) a year

How does a lunar eclipse occur? Moon passes into the Earth’s shadow Earth is between the sun and the moon Only during the Full moon phase

How does a solar eclipse occur? Earth passes into the moon’s shadow Moon is between the Earth & Sun Only during the New Moon phase

What are tides? The rising and falling of our ocean waters along our coast What causes tides? The Sun’s & moon’s gravity