Centuries: 8th century - 9th century - 10th century
Decades: 770s 780s 790s 800s 810s - 820s - 830s 840s 850s 860s 870s
Years: 818 819 820 821 822 - 823 - 824 825 826 827 828
... from the galaxy's redshift z using the formula v ≈ zc where c is the speed of light.
However, only the velocity due to the expansion of the universe should b ...
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