1. Bellwork 9/13 Please hand in:  Old bellwork sheet (if you haven’t already)  Timeline activity Safety contracts Then, grab a new bellwork sheet 
NASA receives billions of dollars for space exploration and research.
In your opinion, is it worth it? Why or why not?

2. Quick Discussion
In a small group of 3-4, please discuss the following questions and outline your answers on a whiteboard
What information did you find interesting or compelling?
What did you have questions about?
Is studying space worth the money we spend?
Please, be prepared to share out what your group discussed.

3. Bellwork 9/15 Happy Friday!! 
In your own words, what causes the phases of the moon?

4. Announcements
Today: Finish Modeling Lab & Discuss, Begin Constellations and Positions
Tuesday 9/19: Lab Quiz (2 questions), Celestial Sphere computer simulation
Thursday 9/21: Stellar Parallax notes & activity
Monday 9/25: Review, Begin Unit 2
Wednesday 9/27: Unit 1 Test

5. Lab Grade 3 components: Working in the lab & collecting data
Working through the analysis questions
Lab Comprehension Quiz
 These will be short (1-3 questions) and will be very similar to the lab analysis questions

6. Modeling Lab

7. Pareidolia--the tendency to perceive a specific, often meaningful, image in a random or ambiguous visual pattern

8. People of the past used this phenomenon to designate locations & positions in the night sky.
Why would they care to do that?

9. Constellations A recognizable pattern of stars in the sky
Used to separate & locate regions of the sky
88 constellations
They were not all designated at one time

10. Constellations Bayer System System of labeling stars
First for Brightness
Using Greek alphabet
α Brightest
β 2nd Brightest
And so on

11. Celestial Sphere
Stars appeared to move around a fixed point and rotate around Earth
We now know that these “star trails” are due to the Earth’s rotation…not the stars’.

13. Celestial Meridian:
Divides the sky in half from north to south.
Zenith:
Bisects the meridian
This point never changes on the celestial sphere, but from the observers’ point of view, the stars at the zenith change
“Actual” zenith vs. “local” zenith
How do we tell “what’s what”?

14. Locating Objects in the Sky: There are 2 ways to look at it…
1. Equatorial system of location
Two location components
Declination – the angular distance north or south of the celestial equator
Measured in degrees 
Right ascension – the angular distance measured eastward along the celestial equator from the position of the vernal equinox
Measured in hours & minutes 

15. Right Ascension (or "RA") and Declination (or "Dec") are global coordinates
any particular star has the same RA and Dec for all observers on Earth, and that position remains the same, night after night.

16. Locating objects in the night sky: Local Coordinates
2. Altitude and Azimuth
local coordinates
each observer sets up his own reference frame
Altitude and Azimuth of a given star will change over just a few minutes as the star appears to move across the sky

17. Ecliptic Zodiac The apparent path of the sun through the stars
The broad belt of constellations that lie along the ecliptic
12 total constellations

18. Anatomy of a Planisphere:
Inner ring: time of day
Declination: Degrees in “viewing window”
Middle ring: Months & Days
Outer ring: Right ascension (hours & minutes)

19. How to use a Planisphere
Set the planisphere to the correct day and time
Make sure you’re holding the planisphere in the correct orientation
 “East horizon” on the left, “West horizon” on the right
Find the Declination
Find the Right Ascension (a straight edge can be helpful with this)

20. What the heck am I looking at?!?
Horizon (looking South)
Horizon (looking North)
Directly overhead…or the Zenith

21. Planisphere Practice:
What is the RA & Dec. of Arcturus? (near constellation Bootes)
RA: ~14hr 15min
Dec: ~+20⁰

22. Planisphere Practice:
What is the RA & Dec. of Betelgeuse? (in constellation Orion)
RA: ~6hrs
Dec: ~+8⁰

23. Planisphere Practice:
Set your planisphere to September 16th at 10:00pm. Name a constellation that is RISING (on the East Horizon).
Taurus
Perseus
Aries
Ect…

24. Planisphere Practice:
Set your planisphere to January 12th at 6:00pm. Name a constellation that is SETTING (on the West Horizon).
Sagitta
Cygnus
Capricornus
Ect…

25. Planisphere Practice:
Set your planisphere to February 28th at 8:00pm.
Name a constellation that is close to its ZENITH.
 Zenith = bisecting line of the meridian…
SO divide your “window” in half horizontally and choose a constellation at that bisecting line
Gemini, Auriga, Camelopardalis

26. …There is more than one answer here!
Bellwork 9/15
How do astronomers communicate the location of objects in the celestial sphere?
…There is more than one answer here!

27. Anatomy of a Planisphere:
Inner ring: time of day
Declination: Degrees in “viewing window”
Middle ring: Months & Days
Outer ring: Right ascension (hours & minutes)

28. What the heck am I looking at?!?
Horizon (looking South)
Horizon (looking North)
Directly overhead…or the Zenith

29. Planisphere Practice:
What is the RA & Dec. of Pollux? (near constellation Gemini)
RA: ~7hr 45min
Dec: ~+28⁰

30. Planisphere Practice:
Set your planisphere to July 15th at 9:00pm. Name a constellation that is RISING (on the East Horizon).
Pegasus Delphinius
Aquarius
Capricornus

31. Planisphere Practice:
What is the RA & Dec. of Sirius? (near constellations Monoceros & Canis Major)
RA: ~6hr 45min
Dec: ~-17⁰

32. Planisphere Practice:
Set your planisphere to April 15th at 11:00pm. Name a constellation that is SETTING (on the West Horizon).
Gemini, Canis Minor, Cancer, Auriga

33. Planisphere Practice:
Set your planisphere to February 28th at 8:00pm.
Name a constellation that is close to its ZENITH.
 Zenith = bisecting line of the meridian…
SO divide your “window” in half horizontally and choose a constellation at that bisecting line
Gemini, Auriga, Camelopardalis

34. Planisphere Practice:
Set your planisphere to October 15th at midnight.
Name a constellation that is close to its ZENITH.
 Zenith = bisecting line of the meridian…
SO divide your “window” in half horizontally and choose a constellation at that bisecting line
Cassiopeia, Perseus

35. Planisphere Practice:
Set your planisphere to March 20th at midnight.
Name a constellation that is close to its ZENITH.
 Zenith = bisecting line of the meridian…
SO divide your “window” in half horizontally and choose a constellation at that bisecting line
Ursa major