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Generate QuizThe reionization epoch occurred approximately between which redshift ranges?
- z=100-50
- z=20-6
- z=3-1
- z=0.5-0
Answer: z=20-6
First stars/galaxies ionized neutral hydrogen between z~20-6 (~180 Myr-1 Gyr post-Big Bang), ending cosmic dark ages; confirmed by CMB polarization and quasar spectra.