1. After School Review Commack High School
Astronomy
After School Review
Commack High School

2. Orbit around an object Spinning on its Axis 365.26 days 15º per hour
Solar System Motions
Rotation
Revolution
Spinning on its Axis
15º per hour
(days)
Orbit around an object
days
(years)
Proof:
Viewed constellations differ each season
Proofs:
Focault pendulum
Coriolis effect
K. Corbisiero 2010

3. Seasons Fall - Sept. 23 – Parallel to Sun Winter Summer Dec. 21
Direct Rays on Equator
12 hours of day and night
Winter
Dec. 21
Tilted Away
Direct Rays on Tropic of Capricorn
9 hours of daylight
Summer
Jun. 21
Tilted Toward
Direct Rays on Tropic of Cancer
15 hours of daylight
Spring – March 21 – Parallel to Sun
Direct Rays on Equator
12 hours of day and night
K. Corbisiero 2010

4. Tilt with respect to the Sun
Reasons for the Seasons:
___________________________________
2. ___________________________________
Tilt with respect to the Sun
Revolution around the Sun
Distance from the Sun is NOT a reason! We are actually closer to the Sun in the Winter!
K. Corbisiero 2010

5. Sun Centered Earth Centered (Geo = Earth) Heliocentric Model
Geocentric Model
Sun
Centered
(Heli = Helium which the Sun is partially made up of)
Earth
Centered
(Geo = Earth)
K. Corbisiero 2010

6. Note that the paths are ALWAYS 23.5° apart!
Path of the Sun
June 21
Direct Rays on Tropic of Cancer
Rises North of East
Sets North of West
Equinox rises due East at 6:00 AM
Equinox sets due West at 6:00 PM
March 21 & Sept 23
Direct Rays on Equator
Polaris at 41º
Sets South of West
Rises South of East
Dec 21
Direct Rays on Tropic of Capricorn
Note that the paths are ALWAYS 23.5° apart!
K. Corbisiero 2010

7. Daylight Length with Respect to Seasons
Winter
Look at the Full Amount of Day & Night to determine the portion of Day and the portion of night in 24 hours.
Season is ______________ in N.H.
Earth is tilted AWAY from Sun
Equator gets 12 hrs day & night
North Pole gets 6 months night
Summer
Season is ______________ in N.H.
Earth is tilted TOWARD Sun
Equator gets 12 hrs day & night
North Pole gets 6 months day
K. Corbisiero 2010

8. What time is it at point X?
It would be Noon here since the Sun would be highest in the sky for people on Earth
It would be Midnight here
6:00 PM (Sunset)
6:00 AM (Sunrise)
It is closest to 6:00 PM since the Earth is just entering into darkness at that point. You MUST look at where the Sun is in relation to the Earths rotation.
K. Corbisiero 2010

9. Changes based on the height of the sun in the sky
Shadows S
Our shadow is to the North because the Sun is always in the South! N
Seasonal Changes
Longest shadows in the winter
Shortest shadows in the summer
Daily Changes
Longest shadows near sunrise and sunset
Shortest shadows at Noon
Changes based on the height of the sun in the sky
K. Corbisiero 2010

10. Eccentricity of an Ellipse
Calculation: Formula ESRT’s pg 1
Note: there are NO units
The value must be between 0 and 1
0 is a perfect circle(least elliptical)
1 is a straight line (most elliptical)
Increasing Eccentricity
More eccentric is more elliptical!
K. Corbisiero 2010

11. Eccentricity of an Ellipse
Drawing an Ellipse
K. Corbisiero 2010

12. Calculate the Eccentricity of the Ellipse
Distance between Foci
Eccentricity =
Length of major axis
1.1 cm
4.3 cm = =
0.256
NOTES:
Measure VERY Accurately!
Answer must be to thousandths place
There are NO units!
K. Corbisiero 2010

13. More: Farthest = Least Closest = Greatest Gravity Gravity Velocity
Apparent Diameter
Closest = Greatest
Gravity
Velocity
Apparent Diameter
K. Corbisiero 2010

14. Solar System Data Table – page 15 ESRT’s
Use to:
Order of the planets
Compare sizes of planets
Determine distances between planets and the Sun
Days and Years of all the planets
Eccentricities of planets
Density and Mass of planets
NOTE: Asteroid belt is between Mars & Jupiter
Years
Days
K. Corbisiero 2010

15. A C E G A Phases of the Moon
Full Moon Position
Lunar Eclipse May Occur
New Moon Position
Solar Eclipse May Occur
Identify which letter shows the position of the moon that each phase would be viewed from Earth: A C E G A
K. Corbisiero 2010

16. Tides NeapTides Spring Tides
They occur due to the gravitational attraction of the Moon and Earth.
High Tides will occur on the side of the Earth where the Moon is (and on the opposite side too).
Spring Tides
NeapTides
Highest Highs, and the lowest Lows
Occurs during full and new moon phases only because the gravity of the Sun and the Moon work together
More gravity = higher tides
Lowest Highs and Highest Lows
Occurs during quarter Moons when the Suns and the Moons gravity work against each other
H = High Tide
L = Low Tide
H = High Tide
L = Low Tide
Sun Gravity + Moon Gravity
Extra High tides, and Extra Low Tides
Moon Gravity – Sun Gravity
NOTE: The Moons gravity has more effect than the Suns only because it is closer!
K. Corbisiero 2010

17. Solar & Lunar Eclipses
They do not occur every month because the moons orbit is tilted.
Solar Eclipse
Lunar Eclipse
Earths Shadow darkens the Moon
The Moon blocks the Sun from the Earth
May occur only during a Full Moon
May occur only during a New Moon
K. Corbisiero 2010

18. Did you know: We only ever see ONE side of the moon!! Why?
Because the moons rotation is equal to its revolution!

19. Stars Hottest Coolest Giants Dwarfs Hottest Coolest
Characteristics - Page 15 ESRT’s
Use to:
Determine how hot a star is by its color
Blue is __________, Red is ___________
Determine the stage of a star in its life
Early = ________________
Intermediate = _______________
Late = ________________
Luminosity is how bright the star is compared to the Sun.
If it is higher than the Sun on the chart, it is brighter and emits more energy
If it is lower than the Sun on the chart, it is duller and emits less energy
Hottest
Coolest
Main Sequence
Giants
Dwarfs
Hottest
Coolest
K. Corbisiero 2010

20. Star Trails Polaris is in the center!
This is what the stars would look like IF the Earth DID NOT Rotate!
Pictures of stars taken with time lapse photography. The pictures are superimposed onto one picture to see how the star appears to move in the sky over time.
The length of time can be determined because every 15 equals 1 hour.
This is how star trails appear in the New York. Polaris is in the center of the star trails and all stars appear to move around Polaris.
How long was the sky to the right photographed?
Looking at star trail 1, 90° - 30° = 60/15° per hour = 4 hours!
K. Corbisiero 2010

21. Our Galaxy The Milky Way A Spiral Galaxy
Our Solar System is one of Billions of Solar Systems in our Galaxy
Our Galaxy is one of Billions of Galaxies in our Universe
Our Solar System is Here
Side View
Top View
K. Corbisiero 2010

22. Universe Galaxies LARGE The Universe
The Universe is made up of Billions of Galaxies
Galaxies
Solar Systems
Draw one symbol inside the other starting with the part of our Universe that is the largest. Each shape should be inside of another shape.
Planets
Moons
small
K. Corbisiero 2010

23. The Big Bang Theory The Big Bang Occurred about 15 billion years ago
(note our Solar System is only 4.6 billion years old)
Proof the Universe is Expanding:
1. Cosmic Background Radiation
2. The Red Shift Effect
K. Corbisiero 2010

24. Red & Blue Shift Blue End Red End Red Run Away, Blue Come’n Play
Every Element has its own spectral line ‘signature’ here on Earth (standard) – no two elements have the same one.
When we look at distant galaxies, the spectral lines are shifted toward the red end of the visible spectrum because they are moving away from us.
If something is shifted toward the blue end, it is coming towards us.
Blue End
Red End
K. Corbisiero 2010

25. RED RUN AWAY BLUE COME’N PLAY
All Galaxies are MOVING AWAY from each other in all directions outward from the center of the Universe!
RED RUN AWAY
BLUE COME’N PLAY
If see a red shift, object is longer wavelength and moving away from us
If see a blue shift, object is shorter wavelength and moving toward us
K. Corbisiero 2010

26. The End