1. Astronomy Notes The Universe ©Mark Place, 2008-2009
Revised 2009

2. How Old is the Universe?
Astronomers estimate that the universe is somewhere between 12 and 14 billion years old. To put this in perspective, the Solar System is thought to be 4.5 billion years old and humans have existed as a genus for only a few million years.

3. What is the Big Bang Theory?
The universe started as a single point.
That point was extremely dense.
It became unstable and exploded outward.
Today the universe continues to expand.

4. What is the Doppler Effect?

5. The Doppler effect – As a star is moving away from us it appears RED because the wavelength of the waves is increasing. If a star is moving closer to us it appears BLUE because the wavelength of the waves would be decreasing- RED shift or BLUE shift. Stars appear red-MOVING AWAY!

6. Evidence for the Big Bang
(1) The Doppler Effect

7. Shifts in the Electromagnetic Spectrum
Doppler Effect ~~>
Red Shift = stars moving away
Blue Shift = stars moving towards

8. Evidence for the Big Bang
(2) Cosmic Background Radiation

9. Stars
©Mark Place,

10. What are the main classifications of stars? Blue Supergiants
Red Giants
Main Sequence
White Dwarfs
Red Dwarfs
ESRTs p15

11. characteristics are used to
What two
characteristics are used to
classify stars?
Luminosity
Temperature
ESRTs p15

12. What type of star is our
Sun classified as?
ESRTs p15
Main Sequence

13. How do stars generate their energy?
Hydrogen
Helium
Hydrogen
Nuclear Fusion

14. Our
Solar
System
©Mark Place,

15. The total mass of all the asteroids is less than that of the Moon.
rocky objects with round or irregular shapes
lie in a belt between Mars and Jupiter
The total mass of all the asteroids
is less than that of the Moon.

16. Comet
A comet is a body of ice, dust and small rocky particles which orbits the Sun. When close enough to the Sun, a comet exhibits a visible tail. The popular Halley's comet next scheduled pass by the earth is in 2062.

17. shooting stars A meteor is a bright streak of light in the sky
(a "shooting star" or a "falling star")
produced by the entry of a small meteoroid
into the Earth's atmosphere

18. The Planets

19. Draw a line across the table between
the terrestrial and jovian planets and label.
terrestrial
jovian

20. Which are more dense?
Jovian or terrestrial

21. Which have more moons ?
Jovian or terrestrial

22. Which have longer periods of revolution?
Jovian or terrestrial

23. Which are larger in size on average ?
Jovian or terrestrial

24. Which planet has the longest day?
Venus

25. Which planet has the longest year?
Neptune

26. How are the orbits of the planets described?
slightly, eccentric ellipse
eccentricity website

27. Which planet has the least
perfectly circular orbit?
Mercury

28. Which planet has the most
perfectly circular orbit?
Venus

29. Calculate the eccentricity
of the ellipse below:
length of major axis
Formula:
eccentricity = distance between foci
length of major axis

30. When does a planet move
slowest in its orbit?
When furthest
from Sun
When does a planet move
fastest in its orbit?
When closest
to Sun

31. Kepler's Second Law
Area A =
Area B
Area C
eccentricity website

32. Explain the difference between the geo- and helio-centric
models of the solar system.
Helio-centric
Geo-centric
Earth-
centered
Sun-
centered

33. Earth Motions Astronomy ©Mark Place, 2008-2009

34. How long is one rotation of Earth?
Earth's Motions
How long is one rotation of Earth?
One day
How long is one revolution of Earth?
One year

35. Rising and Setting
of the Sun
Rotation
Rising and Setting
of the Moon
Movement of Stars
through the sky
Revolution
Changing
Constellations
The Seasons

36. Seasons Earth tilted away from sun in winter
Earth tilted towards sun in summer
Earth tilted away from sun in winter
Seasons
Sun highest in sky in summer and lowest in sky in winter

37. Earth's rate of rotation?
How do you calculate
Earth's rate of rotation?
One rotation = 360°
Time for one rotation = 24 hours
360° ÷ 24 = 15°/hr

38. How many degrees did the stars move
from diagram 1 to
diagram 2?
30° (2 hours x 15°)

39. It’s the only one that didn’t move
How can you find
Polaris?
It’s the only one that didn’t move

40. Because Polaris can only been seen in the North
What hemisphere
must you be in? Why?
Northern
Because Polaris can only been seen in the North

41. What direction must
you be looking?
North

42. What direction do
the stars appear to
move? (Look at diagram)

43. What causes the
stars appear to move?

44. Evidence for Rotation
Foucault Pendulum
Coriolis Effect

45. Evidence for Revolution
Changing Constellations
Parallax -movement of stars

46. Phases
of the
Moon

47. What causes
the phases
of the moon?
The moon's
revolution
around Earth.

48. 27.3 days How long does one revolution of the moon take? How long does
one rotation of
the moon take?

50. What phenomenon
does this explain?
We only ever see one
side of the moon.

51. Why does the moon
rise later each day?
because as the Earth
rotates, the moon
revolves

52. What phase of the moon is this?
New
Gibbous
New
Crescent
3rd
Quarter

53. Approximate Times of Moonrise and Moonset
 moonrise   
moonset
new moon
06:00 AM
06:00 PM
waxing crescent
09:00 AM
09:00 PM
first quarter
12:00 PM
12:00 AM
waxing gibbous
03:00 PM
03:00 AM
full moon
waning gibbous
third quarter
waning crescent
How many hours is the
moon visible each day?
12 hours

54. What is "waxing"?
more of the moon's
surface can be seen

55. What is "waning"?
less of the moon's
surface can be seen

56. The phases of the
moon are what type
of event?
Cyclic

59. A Total Solar Eclipse over Turkey

60. solar and lunar eclipses?
What’s the
difference between
solar and lunar eclipses?
Solar
Lunar
Earth goes
into moon’s
shadow
moon goes
into Earth’s
shadow

61. New Moon
Eclipses
Full Moon

62. Solar Eclipse 2009

63. Solar Eclipses through 2020

65. Lunar Eclipse 2009

66. solar and lunar eclipses
Why don’t we have
solar and lunar eclipses
every month?
The moon’s orbit is
tilted 5° from the
Earth’s orbit.

67. Our Galaxy- The Milky Way
                        
The End