1. Pg Feb. 4, 2013
Focus: Gravity and the Solar System
Objective: 6.E.1, analyze the affect of gravitational pull and how it changes depending on the distance and mass of the object
EQ: What is gravitational pull and how does it affect our solar system?
HW: lesson review questions
Warm Up: self evaluation

2. LAST PICTURE IS GLOBULAR CLUSTER
The Journey Resumes!
For as long as there have been humans on earth, we have gazed into the night sky and wondered:
How far away is the moon?
What are planets and comets?
What are the stars, and why do they shine?
Question answers:
Earth – Moon Distance 384.4x103km. Is it really made of green cheese? Or something more geological?
Planets are “wandering stars.” Comets are bad omens? Or something else?
Those “fixed” pin-points of light? Do they really fall down to Earth as “Shooting Stars?” What is the closest star? (Anyone?)
We are setting foot on a grand adventure to expand our knowledge about these and other astronomical objects.
Consider yourself explorers hunting for the treasures of the universe. We are “prospecting” the heavens to uncover its many facets.
LAST PICTURE IS GLOBULAR CLUSTER

3. Our Solar System
From
This is a montage of planetary images taken by spacecraft. Included are (from top to bottom) Mercury, Venus, Earth (and Moon), Mars, Jupiter, Saturn,Uranus and Neptune. The spacecraft responsible for these images are as follows:
Mercury was photographed by Mariner 10.
Venus was imaged by the Magellan spacecraft's radar.
Earth and its Moon were photographed by Galileo.
Mars Global Surveyor took the image of Mars.
Jupiter was photographed by Cassini as it traveled to Saturn.
Saturn, Uranus and Neptune images were taken by the twin Voyager spacecraft.
Pluto is not shown. No spacecraft has visited Pluto and it is too small and distant for good photography.
The inner planets - Mercury, Venus, Earth, Moon, and Mars - are roughly to scale to each other; the outer planets - Jupiter, Saturn, Uranus, and Neptune - are roughly to scale to each other. But the actual size differences between the inner and outer planets is not to scale. Actual diameters:
Sun 1,390,000 km
Mercury 4,879 km
Venus 12,104 km
Earth 12,756 km
Moon 3,475 km
Mars 6,794 km
Jupiter km
Saturn 120,536 km
Uranus 51,118 km
Neptune 49,528 km
Pluto 2,390 km
In our solar system, eight planets circle around our Sun. The Sun sits in the  middle while the planets travel in circular paths (called orbits) around it.

4. What is a planet? A body that orbits a star
Big enough to create its own gravity
Has a round shape
Has its own orbit

5. Outer Planets Large! Gases and liquids No solid surface
May have a small solid core
Tumultuous atmospheres - rapid winds, large storms
Rotate relatively quickly

6. Inner Planets
“Terrestrial Planets”
Rocky
Dense
Metal cores (iron)

7. What about Pluto? Is Pluto a planet? Why?
No. Pluto is not a planet. Pluto is a dwarf planet, because its orbit overlaps with Neptune. Pluto does not have its own orbit.
Information on Pluto at

8. Kuiper Belt Disk of debris at the edge of our Solar System
Pluto is a KB Object
Image from
Information from The Nine Planets:

9. The Solar System
Sun

10. The Solar System
Sun
Mercury

11. The Solar System
Sun
Mercury
Venus

12. The Solar System
Sun
Earth
Mercury
Venus

13. The Solar System
Sun
Mars
Mercury
Venus
Earth

14. The Solar System
Sun
Jupiter
Mars
Mercury
Venus
Earth

15. The Solar System
Sun
Saturn
Jupiter
Mars
Mercury
Venus
Earth

16. The Solar System
Sun
Uranus
Jupiter
Saturn
Mars
Mercury
Venus
Earth

17. My Very Excellent Mother Just Served Us Nachos.
The Solar System
Sun
Neptune
Jupiter
Saturn
Uranus
Mars
Mercury
Venus
Earth
My Very Excellent Mother Just Served Us Nachos.

18. http://video. nationalgeographic

20. Gravity
Gravity- an attractive force between any two objects, affected by their size and the distance between the two objects.
Definition
Force of attraction between two bodies, proportionate to their two masses and inversely proportionate to the distance between them
So What?
Sun pulls the Earth towards it
G R A V I
T Y

21. Mass Affects Gravity
The bigger/more mass an object, the higher the gravitational force it exerts.

22. Gravity on Different Planets

23. Distance Affects Gravity, too.
The closer two objects are, the higher the gravitational pull they experience.

24. 2 Things Affect Gravity
SIZE/MASS and DISTANCE The bigger the objects, the more gravity they have. The closer two objects are, the more gravity they exert on each other.

25. http://player. discoveryeducation. com/index. cfm
INERTIA

26. The Moon
Inertia keeps the moon moving in a straight line (resisting changes to motion).
Gravity pulls it towards Earth.
Combined, they pull the
moon in a circular orbit
around the Earth.
So, the 2 factors that keep
the moon orbiting the Earth
are gravity and inertia.

30. Why does the moon have phases?
The revolution of the Moon around the Earth causes the Moon to appear to have phases.
NSF North Mississippi GK-8

31. TICKET OUT Why do the planets revolve around the sun?
What would happen without gravity?
What is gravitational pull and how does it affect our solar system?