The slideshow from class. Us it to review for your test. Go over the notes and questions too.

1. The Size of the Solar
System

2. Radar
• The first known radar was built in 1935.
• It emitted mircowaves which allowed us to
determine the distance to an object by timing how
long it takes for the microwave to be reflected
back to source.
• Radar lets us determine the size of celestial
bodies and their distance from us.

3. • Bats use radar to locate obstacles and prey.
• Bats produce a particular sound and then listen for
its echo.
• We cannot hear a bats “radar” sound

4. The Solar System:
Like a Grain of Sand on the
Beach
Read page 25 together.
What is the speed of light?
• 300 000 km/s or 300 000 000 m/s
• This is how far light goes in one year:

5. • Our galaxy is called the Milky Way.
• What is a galaxy?
• A group of stars and other celestial bodies.
• The Milky Way is over 100 000 light years wide!!
• How long does light from the Sun take to reach
the Earth?
• 8.3168708 minutes.
• Rounded off, let's say 8 minutes and 18
seconds.

7. What happened to the space
shuttle, Columbia?
• Exploded during takeoff on February
1, 2003.
• By recovering debris from the space
shuttle and analyzing the debris they were
able to identify which part of the space
shuttle exploded.

8. The Experimental Method
• Galileo built his telescope in 1606. He was the first
to use it to observe the sky.
• Things he discovered:
• Saturn’s Rings
• Jupiter’s satellites
• The Phases of Venus
• And much more!!

9. • His observations of Venus proved
that the Earth travelled around the
Sun.
• His telescope made these
observations possible.
• By improving technology, we are
able to continue improving
scientific knowledge.
• We will read pages 433 - 435

10. How to Apply the
Experimental Method
• There are 5 steps:
1. I observe…
2. I develop a research question…
3. I define the variables…
4. I experiment…
5. I analyze my results and present them>

11. The Solar System:
Like a Grain of Sand on the
Beach
Read page 25 together.
What is the speed of light?
• 300 000 km/s or 300 000 000 m/s
• This is how far light goes in one year:

12. • Our galaxy is called the Milky Way.
• What is a galaxy?
• A group of stars and other celestial bodies.
• The Milky Way is over 100 000 light years wide!!
• How long does light from the Sun take to reach
the Earth?
• 8.3168708 minutes.
• Rounded off, let's say 8 minutes and 18
seconds.

13. The Sun
• The closest star to the
Earth.
• A ball of gas made
primarily of hydrogen
(H)
• The Sun is 5770 °C on
the surface
• The Sun is 15 000 000
°C at the center!

14. • The Sun is part of our
galaxy, the Milky Way
• What is a galaxy?
• A group of planets and
other celestial bodies.

15. • The Sun acts like a huge nuclear reactor turning
hydrogen (H) into helium (He).
• It is thought the Sun will be active for another 5
billion years.
• At this time, the Sun’s diameter will increase and it
will swallow the Earth!!
• It will be 2000 °C on Earth.
• Then the Sun will cool and die.

16. Ambulance Sirens
• The Doppler Effect is what we hear as the
s]ambulance gets closer and then moves away.
• The siren seems to become more high pitched as
the ambulance gets closer and less high pitched
as it moves away.
• Why?
• Shall we listen?

17. • Sound waves move like waves on the water.
• As the waves move away from the point of contact
the space between the waves becomes larger.
• This means they are more spread out in the air.
• As the sound waves get farther apart the sound
has a lower pitch.

18. • The Doppler Effect and light waves
• Light waves also create circular waves
• Light waves that are close together correspond to
violet light.
• Light waves that are farther apart are correspond
to red light.

19. • As the planets
move farther
away, they
become “red”

20. E R E R L N I
D A L E U DI O
N L E E G L
G O N O E
E W T
• How can we remember the order of the colors?