Doppler waves

Doppler Effect

• Divide the change of wavelength by the original wavelength
• wavelength we observe/wavelength we should observe = velocity of object (toward + or away - ) from us/speed of source
• as objects move away, wave length gets longer

Telescopes

• refracting:
• Newton was the first to use a reflecting telescope
• reflecting:
• uses a secondary mirror
• resulting image is always smaller than original

shows more light and detail

• light-gathering power
• related to area of lens
• resolving power
• related to the diameter and wavelength, bigger is better!