Prelesson Vocabulary Rotation and Revolution Rotation the amount

Pre-lesson Vocabulary: Rotation and Revolution • • Rotation = the amount of time that it takes for an object to spin on its axis Revolution = the amount of time that it takes an object to revolve, or go around, another object.

Objectives • Compare historical models of the solar system. • Compare and contrast the characteristics of objects in the Solar System • Relate the role of gravity to the formation and motion of planets, stars, and solar systems

Agenda I do: Guided notes and video discussion. We do: Reading passage and table analysis. You do: RAFT and Exit ticket

Essential question How are the planets in the solar system similar? How do they differ from each other?

The Solar System SC. 8. E. 5. 7 Compare and contrast the properties of objects in the Solar System including the Sun, planets, and moons to those of Earth, such as gravitational force, distance from the Sun, speed, movement, temperature, and atmospheric conditions.

Essential Question: How are the planets in the solar system similar? How do they differ from each other? Helio versus Geo Why do we use models to represent the solar system?

How is the heliocentric model different to the geocentric? How are the alike? • Video discussion

A solar system (a. k. a. planetary system) = • A star, with planets or other objects (ex. comets) revolving (going) around it. The solar system is heliocentric, with the sun in the center.

At one point, we thought the solar system was geocentric • • What does “geo” mean? This model is incorrect because it places the Earth in the middle, and has the planets revolving around it.

How did the solar system form? • It formed 4. 6 billion years ago • It took 100 million years • It formed from the collapse of a GIANT cloud of gases, rock, ice, and other materials. – Gravity pulled materials together to form a cloud. As the cloud collapsed, it started to rotate and flatten into a disk with a hot center. – The hot center started to undergo nuclear fusion, and the sun was born. Most of the mass went into this. – Other orbiting rocks, ices, and gas collided and stuck together to form planets. Those planets had a gravity large enough to round them out.

How does mass and distance affect gravity? Lets see it in our Solar System!

Solar System If all these planets were at the same distance from the Sun, which one would experience more gravity? Why?

Solar System If all these planets had the same size, which one would experience more gravity from the Sun? Why?

The Star in our Solar System: the Sun • The sun spins, but it does not revolve around anything. The Planets = My Very Energetic Mother Just Served Us Nachos

Inner Planets • Small • Dense (very heavy, would sink in water) • Rocky surface, and metal cores • Also called “terrestrial”

Mercury • • The closest planet to the Sun No atmosphere = extreme temperatures Rotation: 1 day = 59 days Revolution: 1 year = 88 days

Venus • Extremely thick atmosphere contains a lot of carbon dioxide. This creates an extreme greenhouse effect, and makes Venus the hottest planet. • Rotation: 1 day = 243 days • Revolution: 1 year = 225 days

Earth Rotations: 1 day= 24 hours Revolution: 1 year= 365 days 1 Moon The atmosphere makes our planet suitable for life.

Mars • Called the “Red Planet” • Rotation: 1 day = 25 hours • Revolution: 1 year = 1. 88 years • Moons: 2 (Phobos and Deimos) • Curiosity is the name of the rover that was most recently sent to Mars.

Uranus Jupiter Saturn Outer planets Neptune

• The Outer Planets Their orbits are farther out Colder than the inner planets Known as giants (not as dense as inner planets) LARGE

Jupiter • • • Largest planet Famous for its “Great Red Spot” which is actually a storm that has been observed since the 1800 s! Rotation: 1 day = 10 hours Revolution: 1 year = 12 years 50 moons

Saturn • • • Density is lower than water, so it could actually float Has rings made of ice and rocks Rotation: 1 day = 10 hours Revolution: 1 year = 29 years Moons: more than

Uranus • • • Turquoise colored because of methane Appears to rotates on it’s side Rotation: 1 day = 17 hours Revolution: 1 year = 84 years Moons: more than 27

Neptune • • • 2. 8 billion miles away from the Sun Blue colored Rotation: 1 day = 16 hours Revolution: 1 year= 165 years Moons: more than 13

Essential Question: How are the planets in the solar system similar? • They all revolve around the sun (1 year) • They all rotate on their axes (1 day) • They all travel in elliptical, not circular, orbits.

Essential Question: How are the planets in the solar system different from each other?

1. The planets orbit the sun in the same direction, but at different speeds. The farther the planet, the slower it travels around the sun.

2. Planets differ in composition, size and density • Inner planets • Outer planets (Gas Giants) Jupiter, Saturn, Uranus, and Neptune (Terrestrial planets) Mercury, Venus, Earth, and Mars. • Rocky • Gassy • High Density • Low Density • Small • Large

3. Revolution Period The farther a planet is from the sun, the longer its revolution takes

4. The planets differ in size, but in general the outer planets are much larger than the inner planets. The larger the planet, the stronger its gravitational pull

5. The farther from the sun, the colder the temperatures.

Guided Practice: Reading Selection and Table Analysis

Independent Practice

Exit Slip on your own!