Catalyst:

1.Mouths are quiet.

2.Get your binder and begin the quick review section of your notes.

3.Raise your hand if you need something.

Quick Review1. Skin covers the outside of the human body. What type of cells makes up skin? Epithelial 2. The brain sends signals to control muscles and receives signals from sensors in the skin. On which type of cells do these signals travel? Neurons3. Which cells in the body fight off pathogens? White blood cells

Quick Review4. Which flat, disc shaped cells contain hemoglobin for carrying oxygen? Red blood cells 5. Osteocytes make a hard substance from calcium and phosphate which help support the body. These cells make bone.

Earth and SpaceLesson 7.12 – The Doppler Effect and

Astronomy

I can explain the Doppler Effect, how this causes Red Shift, and the implications for astronomy. (4f)

1. If a moving object is producing waves (electromagnetic or sound), the wavelengths of these waves will be changed by the object’s motion.

I can explain the Doppler Effect, how this causes Red Shift, and the implications for astronomy. (4f)

a. If an object is moving toward the observer, the waves will be compressed (pushed together) and the wavelength will decrease.

1) For a sound wave, this will cause ahigher pitched sound.2) For EM waves, this will cause the color to shift toward the blue end of the electromagnetic spectrum. This is called blue shift.

I can explain the Doppler Effect, how this causes Red Shift, and the implications for astronomy. (4f)

b. If an object is moving away from the observer, the waves will spread apart and the wavelength will increase.

1) For a sound wave, this will cause a lower pitched sound.2) For EM waves, this will cause the color to shift toward the red end of the electromagnetic spectrum. This is called red shift.

I can explain the Doppler Effect, how this causes Red Shift, and the implications for astronomy. (4f)

c. This is called the Doppler Effect.

2. The Doppler Effect gives astronomers many new tools for studying the universe.

a. Scientists can determine if a star or galaxy is moving toward us or away from us and how fast it is doing so by studying the red or blue shift of the object.b. Scientists have determined that the universe is expanding because the oldest stars are exhibiting red shift.

Guided Practice Video

  #1 #2 #3Predicted Green Blue UV LightObserved Orange Infrared X-RayType of Shift

Red Red Blue

Object Direction

Away Away Toward

Color Wavelength

violet 380–450 nm

blue 450–475 nm

green 495–570 nm

yellow 570–590 nm

orange 590–620 nm

red 620–750 nm

  #4 #5 #6Predicted Infrared Radio Green Observed Microwave Infrared UV LightType of Shift

Red Blue Blue

Object Direction

Away Toward Toward

Color Wavelength

violet 380–450 nm

blue 450–475 nm

green 495–570 nm

yellow 570–590 nm

orange 590–620 nm

red 620–750 nm

I-N-D-E-P-E-N-D-E-N-TDo you know what that

means?

Exit Ticket(5 questions)

1. A star near Earth would usually produce blue light but its light is perceived on Earth as green. Which of these describes what is occurring?

A. Red shiftB. Blue shiftC. No change in light wavelengthD. It is not possible to determine

2. A star producing green light is moving away from an observer, which of these describes what will occur?

A. Red shiftB. Blue shiftC. No change in light wavelengthD. It is not possible to determine

3. A plane is producing sound waves. If the plane is moving toward an observer, what will happen to the wavelength of these sound waves?

A. Stay the sameB. Increase in wavelengthC. Decrease in wavelengthD. It is not possible to determine

4. A celestial body is producing 560 nm electromagnetic waves. If it is detected by an observer to have a wavelength of 600 nm which of these describes the relationship between these objects?

A. They are moving toward one another.B. The distance between them is

constant.C. They are moving away from one

another.D. It is not possible to determine.

5. A scientist using an optical telescope measures a yellow light coming from a star. It has the same wavelength as yellow light produced by our Sun. Which of these correctly describes the relationship between these stars?

A. They are moving toward one another.B. The distance between them is constant.C. They are moving away from one another.D. It is not possible to determine.