1. Shooting Stars
• They are not stars; they are meteoroids.
• The “tails” are caused by debris burning up as
it enters the atmosphere.
• Comets are the cause of these meteoroids and
dust; when they pass near the Sun this is the
result.
• There are a number of meteoroid showers
every year.

2. • The Perseids meteor
shower is one of the
most active meteor
shower seen from Earth.
• Occurs around August
12.
• The showers are named
after the constellation
they seem to be coming
from

3. • Certain planes fly at an altitude of 20 000
m or more.
• Carry containers with a special gel used
to trap the dust particles from space.
• The dust is analyzed and gives us a
glimpse into the mysteries of the
universe

4. Average number
Name Period of shooting stars Constellation
per hour
Quadrantids January 1 to 6 40 BoÖtes
Lyrids April 19 to 24 15 Lyra
Aquarids May 1 to 8 20 Aquarius
Perseid July 25 to August 50 Perseus
18
Orionids October 16 to 27 25 Orion
Leonids November 15 to 15 Leo
20
Geminids December 7 to 50 Gemini
15

5. The Earth in Motion
Page 317 to 325
• Read the Overview on page 317.
• What is the Earth’s source of energy?
• It’s internal core!!! We will look at this in more
detail.
• The Sun is also a source of energy for the
Earth.
• How?

6. • Warms the air, the water, and the ground
during the day
• What happens at night?
• The heat dissipates!!
• The changing temperature leads to:
• Erosion
• The water cycle
• Winds
• Sea currents

7. Continental Divide
• Alfred Wegner developed this theory in 1910.
• Proposed that at one time there was a
supercontinent :
• This was 200 million years ago (MYA)
• Our continents are caused by the
fragmentation of Pangaea.
• His idea was not accepted until the 1960’s

8. • A puzzling time!!
• The continents
looked like they
could fit
together.

9. • Wegener
there were
similar rock
formations in
mountain
chains on
different
continents

10. • Fossils were another indication that at
one time the continents were close
together.
• The Mesosaurus is found in South Africa
and Brazil!!!

11. • Lystrosaurus was a small land dinosaur that
appears to have migrated from South
America to Africa.
• It could not swim
• Was/is this possible?

12. • He proposed the idea of a single
immense continent, Pangaea.
• 220 MYA
• The single ocean was called Panthalassa

13. • The supercontinent broke into large pieces
that drifted to there present location.
• Formed the continents and oceans we know
today.
• This is Continental Drift
• The scientific community did not accept
Wegener’s ideas!!!

14. You live on a plate
• Read page 41
• Summarize in your own words.
• Pass in when complete.

15. The Earth’s Internal Structure
• Read pages 294 and 295
• What is a geologist?
• Someone who studies the nature and the
structure of the Earth’s crust.
• They study the composition of the Earth.
• Also analyze rocks, minerals, and fossils.

16. 5 °C
1000 -1800 °C
1800 – 3700 °C
3700 – 4500 °C
Above 4500 °C

17. • In the beginning…
• The Earth was liquid
• The heavy elements, iron (Fe) and nickel
(Ni) combined to form the core.
• The lighter elements, silicon (Si), oxygen
(O)and aluminum (Al) form the mantle and
crust.
• When the Earth’s temperature cooled, the
crust solidified.