1. the study of space, stars, galaxies, planets, etc.
Astronomy
the study of space, stars, galaxies, planets, etc.

2. Rotation=SPIN (1 rotation=1 day=24 hours for Earth)
Earth is tilted on its axis at 23.5 degrees (why we have seasons)
Day/night animation:

3. N I G H T D A Y

4. Revolution=movement around another object
Note: all of our
planets revolve
counterclockwise
orbit is the
PATH the planet
(or moon) takes
as it revolves
shape of orbit is
circular or elliptical (oval)
Ex: one revolution/orbit around the sun=1 year= days
Ex: one revolution/orbit of the moon around the Earth=1 month

5. Earth in Space Earth rotates revolves causing On its axis
Around the sun
causing
Years
Day and night

6. GRAVITY depends on: MASS and DISTANCE INERTIA Brainpop: Newton
Brainpop: Gravity
--elliptical
INERTIA
GRAVITY depends on:
MASS and DISTANCE

7. Earth in Space March=Vernal Equinox September=Autumnal Equinox
Brain Pop: Seasons
Brain Pop: Equinox & Solstice
Earth in Space
March=Vernal Equinox September=Autumnal Equinox
June=Summer Solstice December=Winter Solstice

8. Theories about the center of the universe— make a double bubble
A theory is an explanation of related observations.
Geocentric
EARTH centered
(sun, moon, stars, planets revolve around Earth)
Believed until 1500 AD
Early cultures and Ptolemy
Heliocentric
Sun centered
(planets and comets revolve around the sun)
1500 AD to present
Copernicus*, Galileo, Kepler, Newton
Are either correct? ~ Helio is mostly correct

9. Ptolemaic theory
(geocentric)
Copernicus’s theory
(heliocentric)

10. Review question
What did the geocentric theory state? Is this theory correct?
>>Earth is at the center of the solar system
(incorrect)

11. Big Bang Theory (theory of the formation of the Universe --1950)
matter, time and energy were compressed into an extremely small ball (very unstable)
exploded about BILLION years ago
DYK: Every hour the Universe expands by a billion miles in all directions.
Brain Pop: Big Bang

12. Brainpop: Galileo Discuss:
Universe
Galaxy
Solar System
Planets
make a space timeline:

13. Day #3--Galaxies
Cosmic Zoom

14. Image from Hubble Telescope

15. Galaxy (Brainpop)
a large group of gas, dust, and millions/billions of stars.

16. 3 main shapes : Spiral ~ Ex: Milky Way Elliptical ~ older stars
Irregular ~ younger

17. The Milky Way ~ Brain Pop

18. Milky Way Galaxy (about billion stars) (ly=light year=DISTANCE light travels in 1 year=6 trillion miles)
about 100,000 ly wide and about 2,000 ly thick
we are 30,000 ly from the center (or 250 million billion km)
takes us 230 million years to make one orbit (revolution)
Our closest galaxy is Andromeda Galaxy (2 million ly away)
Spiraling arms
Contains oldest stars
DYK: If every star in the Milky Way was a grain of salt, they
would fill an Olympic sized swimming pool.

19. Milky Way as seen from Earth

20. Our solar system is located in the Milky Way
Our solar system is located in the Milky Way. Which one of the following statements best describes the Milky Way?
A. a nebula containing about 200 billion stars
B. a spiral galaxy containing about 200 billion stars
C. an irregular galaxy containing about 200 billion stars
D. an elliptical galaxy containing about 200 billion stars

21. Where in the Milky Way is our solar system located?
A. in the center of the Milky Way
B. in a nebula in the Milky Way
C. in a spiral arm of the Milky Way
D. in a nova in the Milky Way

22. Questions To what does the Big Bang refer?
an explanation of how the universe began
(AC) The North Star (Polaris) is x 1012 km from Earth. What is this number written in its long form?
4,080,000,000,000 km

23. Galaxies exist in groups called CLUSTERS
Our Milky Way belongs to a cluster of 32 galaxies called the Local Group.
The Milky Way is the second largest galaxy in this group (Andromeda is the largest).
Clusters group together to form superclusters.

25. Great website that shows how big the Universe is
Secret World

26. Review Questions
Which object is the largest: Earth, the sun, the Milky Way Galaxy, supergiant star?
>>the Milky Way Galaxy
Where in the Milky Way Galaxy is the solar system found?
>>in an outer arm
A light year is a unit of _________.
>>distance

27. Our Solar System (includes the sun, 8 planets and their moons, asteroids, comets, meteoroids & other smaller objects)

28. SUPERGIANTS
(on Orion’s shoulder)
GIANTS

29. Our star, THE SUN yellow middle-aged medium-sized
surface temperature of about 6000°C
medium brightness

30. Planets ~ make a double bubble
Inner Planets
also called terrestrial planets
small, dense and rocky
no rings
Mercury
Venus
Earth
Mars
Outer Planets
also called gas giants
all have moons
all have at least one ring
Jupiter
Saturn
Uranus
Neptune

31. Relative size of the planets

32. Brain Pops ~ as time permits
Black Holes
Life Cycle of Stars
Outer Solar System
Constellations