If the Spectrum of a Distant Galaxy Is Observed to Have

question 17

Multiple Choice

If the spectrum of a distant galaxy is observed to have a calcium K absorption line that occurs at a wavelength of 500.4 nm, what is this galaxy's distance if the rest wavelength of this absorption line is 393.4 nm? Assume the Hubble constant is 70 km/s/Mpc.

• A) 720 Mpc
• B) 950 Mpc
• C) 1,200 Mpc
• D) 2,500 Mpc
• E) 3,700 Mpc

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