# Physics of the Earth CP Study Guide Astronomy Part I

Name______Period______Date______

Physics of the Earth CP Study Guide – Astronomy Part I

Final Exam Date:______

1. Explain the heliocentric model.

Heliocentric Model– states that the Sun is the center of the universe

1. Explain the geocentric model.

Geocentric Model- States that the Earth is the center of everything in universe

Planets move in perfect circles around the Earth

1. What are the contributions of the following astronomers:
2. Ptolemy

Geocentric Model– states that the Earth is the center of

everything in universe

•Planets move in perfect circles around the Earth

1. Galileo

•Late 1500s - early 1600s

•Believed Heliocentric Model

•Inventor of telescope

–Observed moons of Jupiter

–Observed phases of Venus

1. Copernicus-

•1500’s Polish astronomer

Heliocentric Model– states that the Sun is the center of the

universe

•Planets move in perfect circles around the Sun

1. Kepler

•Late 1500s, German mathematician

•Planets have elliptical orbits

•Unable to explain why planets orbits were elliptical

1. What is refraction?

Refraction- a change in direction of a wave as it crosses the boundary that separates one medium from another

1. What is reflection?

Reflection- occurs when a light ray travels from an object (such as your body), hits a reflective surface (such as a mirror) and is redirected to your eye. It is the redirection of the light that causes a duplicate image to be created.

1. What is the electromagnetic spectrum?

The Electromagnetic Spectrum is the range of all possible frequencies of electromagnetic radiation.

The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object.

1. Define gravity.

Gravity is the attractive force between two objects

1. What is the difference between mass and weight?

Mass is defined as the amount of matter an object contains.

Weight of an object on earth depends on the force of attraction (gravity) between the object and earth

1. List the phases of the moon and draw them:
1. What is a solar eclipse? What is being blocked out? What phase is the moon in?

#### Moon passes between Earth and Sun

Only see outer layers of sun

### Occurs during new moon

1. What order are the sun, moon and earth in during a solar eclipse? Draw this arrangement.
1. What is a lunar eclipse? What is being blocked out? What phase is the moon in?
• Moon passes into Earth’s shadow
• Reflected light from the moon is blocked, instead moon seems red
• Can only occur during full moon
• Occur slightly more frequently than solar
1. What order are the sun, moon and earth in during a lunar eclipse? Draw this arrangement.

1. Compare and contrast the umbra and the penumbra.

#### Penumbral -The Moon passes through Earth's penumbral shadow.

fainter, less defined, sometimes nonexistent

Umbra-A portion of the Moon passes through Earth's umbral shadow.

dark and more defined

The penumbra is dependent on the umbra

1. Describe the three theories for the formation of the moon.

Capture Theory- Moon caught by Earth’s gravitational pull

Simultaneous Formation Theory- Moon and Earth formed at same general time in same general area

Impact Theory- Earth collided with a Mars-sized object

Materials from collision came together to form moon

Explosion evaporated water

1. What is the most accepted theory for the formation of the moon?

Impact Theory-

Materials from collision came together to form moon

Explosion evaporated water

1. What are tides? What causes tides?

Periodic rise and fall of the level of the ocean.

The moon’s gravity pulls on Earth

Gravity creates build up of ocean water on both

the near and far sides of the Earth

The ocean water build up stays in line with the moon

The ocean level rises and falls every 12 hours

1. Describe a spring tide.

Spring Tide–When the sun and moon are aligned and the tides are HIGHER then normal

1. How are the sun, earth and moon aligned during a spring tide? Draw them.

1. Describe a neap tide.

Neap Tide–When the moon and sun are at right angles and the tides are

LOWER than normal

1. How are the sun, earth and moon aligned during a neap tide? Draw them.

A "neap tide" occurs when the tidal forces of the Sun and the Moon work at right angles to each other, lessening the total effect of the tides. This happens when the Sun, Moon and Earth form a triangle pattern. This happens at the first or third quarter phases of the Moon.

1. What causes the seasons?

The seasons are caused by the tilt of the Earth's rotational axis away or toward the sun as it travels through its year-long path around the sun.

1. Label the diagram below.