1. Saturday, September 22, 2018 WU: Compare a radio wave to a microwave.
a) Which has a higher frequency?
b) Which has a longer wavelength?
Spectrum Analysis
Need colored pencils
Microwave
Radio Waves

2. All missing assignments must be turned in!
To Do
Update SN
Journal Check next week!
HW: Universe CBA Review due tomorrow
Quiz on Monday – SN pages 33-45
All missing assignments must be turned in!

3. $11.00 on Mypaymentsplus Deadline: Thursday, October 5.

4. Goal: Use spectroscopy to determine a star or galaxy’s: Motion
towards or away from you
Relative speeds
Composition
What elements are in it.

5. Color in the above spectrum on your sheet
What color has the longest wavelength?
Shortest wavelength?
What color has the highest frequency?
Lowest frequency?
What color would you expect to see if its wavelength were:
600 nanometers?
450 nanometers?
650 nanometers?
Red
Violet
Violet
Red
Orange
Blue
Red

6. Below are the bright line spectra of four elements and the spectrum of an unknown gas. (Color it in your SN)
Lithium
Hydrogen
Helium
Sodium
Which elements are in the unknown? Explain.
b) Why are you able to exclude the presence of the other elements?
c) Young stars are mostly hydrogen with a small abundance of helium and other elements. Is the unknown a likely spectrum for a young star? Explain your answer.
Hydrogen and Helium. The unknown has all of the hydrogen and helium lines.
The unknown does not contain all of the lines for lithium or sodium
Yes this is likely to be a young star because it contains hydrogen and helium

7. -Spectrums A, B, and C are from identical stars
-Spectrums A, B, and C are from identical stars. -A represents a spectrum from an unmoving star. -B and C show stars in motion with respect to us
A = B= C=
C – Blue shifted (smaller wavelength)
B – Red shifted (longer wavelength)
C, it is shifted farther from original

9. All missing assignments must be turned in!
To Do
Update SN
Journal Check next week!
HW: Universe CBA Review (Due Tomorrow)
Moon Review (Due Monday)
All missing assignments must be turned in!