Objectives 1.1j The shape of Earth, the other planets, and stars is nearly spherical. 1.1a...

Objectives

1.1j The shape of Earth, the other planets, and stars is nearly spherical.

1.1a Earth’s Sun is an average-sized star. The Sun is more than a million times greater in volume than Earth.

1.1c The Sun and the planets that revolve around it are the major bodies in the solar system.

Other members include comets, moons, and asteroids. Earth’s orbit is nearly circular.

1.1d Gravity is the force that keeps planets in orbit around the Sun and the Moon in orbit around the Earth.

Do Now:

What are stars?

Do we have any stars in our solar system?

Solar System of the Sun

Aim: What are the major bodies of our solar system?

1. How is space organized?

a.Universe – all of space and everything in it

-formed during the BIG BANG 10-15 billion years ago

-has been expanding ever since

How did the universe form?

Big Bang

b. Galaxies – clusters of stars (100s of billions)– We live in the Milky Way galaxy– Classified by shape

• Spiral (Milky Way)• Elliptical• Irregular

Looks like a Milky River in the sky

We are in the Milky Way Galaxy, spiral shaped cluster of stars

c. Stars – Huge spheres of glowing gas (mostly hydrogen)– Our sun is only an average-brightness star– There’s billions of stars in the Milky Way (our Sun is

one)– Stars are very far apart and very far away from us– Classified by Size, temperature, and brightness

Checkpoint:

Why does the Sun look so BIG but all the other stars look so small?

Can you list all the planets in our solar system?

d. Solar Systems – – Planets and other space objects revolving

around a star

M V E M J S U N P

List the order of planets…..My

Very

Excellent

Mom

Ann

Just

Served

Us

nachos

How Big is the Universe?

Distances Animation

http://www.classzone.com/books/earth_science/terc/content/visualizations/es2701/es2701page01.cfm?chapter_no=visualization

2. How is our Solar System arranged?

Geocentric Model –

Earth is in the center

Heliocentric Model – Sun is in the center

X

the orbit of the planets around the sun is the shape of an ellipse (slight oval)

3. What causes planets to revolve around the Sun?

a. Inertia– tendency of an object to travel in a straight line -All objects were set in an outward motion during the “Big Bang”b. Gravity– the force of attraction between 2 objects.-Gravity pulls objects toward each other, influencing the direction

they will move.

c. Newton’s 1st law of motion

–an object in motion stays in motion.

d. Gravity and Inertia are balanced or equal forces which keeps us revolving.

Which planet has the longest revolution? Shortest?

The closer the planet to the Sun, the shorter revolution period (year).

On which planets would you be the “younger” than you are now?Why?

4. What two factors affect gravitational attraction?

a. Distance – the closer two objects are, the greater the gravitational attraction between the two objects

b. Mass – the more mass an object has, the greater the gravitational pull it can exert on another object.

Hmm…Which planet has the strongest gravitational force on an object?

Which planet has the least gravitational force on an object?

Will the Sun’s gravity pull more on Mercury or Pluto?– Why?

On which planet would you weigh the most?

6. What else is in our solar system?

-mostly empty space (vacuum)

-moons, asteroids, comets

MoonsSmaller rocky spheres that revolve around

larger planetsAlso called satellitesEarth has one moon.Some planets have many moons.

7. What are asteroids, comets, and meteors?

“Left-overs” from the formation of the solar system that did not get formed into a planet or moon. – Asteroids: rocky irregular

objects• Found in Asteroid Belt- between

Mars and Jupiter

– Comets: small icy bodies of frozen gases “dirty snowballs”• Found in Oort cloud in the farthest

limits of our solar system

– Meteor: interplanetary object that enters Earth’s atmosphere

8. What is the Kuiper Belt?

Group of small solar system bodies made of rock and ice outside Neptune’s orbit.

Summarize: List all the objects found in our solar system:

SunPlanetsMoonsAsteroidsMeteorsComets

http://highered.mcgraw-hill.com/sites/0072482621/student_view0/animations.html#