Cosmology – Page 2 – National Radio Astronomy Observatory

Why are the Milky Way and Andromeda Galaxies Moving Toward Each Other While the Universe is Expanding?

The Andromeda and Milky Way galaxies are moving toward each other due to mutual gravitational attraction. This mutual gravity…

No. When we look at an object in the universe we see that object as it existed when the…

Astronomers observe a regular progression of galaxies which are expanding at progressively higher velocities as they measure galaxies at…

The universe is currently expanding at a rate of about 75 kilometers per second per mega-parsec. If we consider…

Your estimate for the average distance between stars is reasonable. Your estimate for the average distance between galaxies is…

The list of visualizations that you provide are some of the best descriptions of the expansion of the universe. …

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