An Expanding Universe

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An Expanding Universe Redshift, Blueshift and the Doppler Effect EMS Review • The shorter the wavelength, the higher the frequency • The longer the wavelength, the lower the frequency • Red wavelengths of light are longer than blue wavelengths of light • Star composition can be determined by the spectrum of the gases present Doppler Waves • As an object moves away from you, the waves spread out. Wavelength gets longer and frequency decreases. • As an object moves towards you, the waves bunch up. Wavelength gets shorter and frequency increases Doppler Waves • As an object moves away from you, the waves spread out. Wavelength gets longer and frequency decreases. • When dealing with light waves, we say that the object has red-shifted because the waves move towards the red end of the spectrum Red shift, moving away. Doppler Waves • As an object moves towards you, the waves bunch up. Wavelength gets shorter and frequency increases • We say that the object has blue-shifted because the waves move towards the blue end of the spectrum. Blue shift, moving towards. How can we tell that the universe is expanding? https://www.youtube.com/watch?v=FhfnqboacV0H ow can we tell that the universe is expanding? As an object moves away from you, the object’s spectrum of gases shifts to the red side of the spectrum Shifting Spectrums Red shift/Blue shift Practice Blue Red • Nearby Star VENUS Which galaxy or Andromeda Galaxy planet is moving at Bernard’s Galaxy the same speed as the Bear Galaxy nearby star? Venus SR - 5 Red shift/Blue shift Practice What Blue Red Nearby Star galaxies or planets are moving Andromeda Galaxy toward the nearby Bernard’s Galaxy star? Bear Galaxy • Andromeda Venus SR - 5 Red shift/Blue shift Practice Blue Red Nearby Star What galaxies or planets are Andromeda Galaxy moving away the nearby Bernard’s Galaxy star? Bernard’s, Bear Galaxy Bear, SR-5. Venus SR - 5 Red shift/Blue shift Practice Blue Red Nearby Star Is the Andromeda Andromeda Galaxy galaxy red or blue shifted? Bernard’s Galaxy Blue Shifted Bear Galaxy Venus SR - 5 Red shift/Blue shift Practice Blue Red Nearby Star Which galaxy or planet is Andromeda Galaxy moving fastest away Bernard’s Galaxy from the nearby star? Bear Galaxy Benard’s it is the Venus most red shifted SR - 5 Red shift/Blue shift Practice Blue Red Which galaxy Nearby Star or planet is moving the slowest away Andromeda Galaxy from the nearby star? Bernard’s Galaxy SR- 5 Bear Galaxy Venus SR - 5 .

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