Take the 2-minute tour ×
Astronomy Stack Exchange is a question and answer site for astronomers and astrophysicists. It's 100% free, no registration required.

If I stood on a theoretical earth at the time that galaxies were just starting to form, what would the sky have looked like?

Due to the smaller size of the universe would it have been densely packed with objects? If yes, what might I have seen?

share|improve this question

1 Answer 1

In early times of galaxy formation you would have seen a sky similar to this Hubble Extreme Deep Field image. A sky filled with small, irregularly shaped, young galaxies and galaxy predecessor fragments (sub-galaxies). Galaxies probably formed bottom-up from smaller fragments.

Further back in time it would have been dark. Hydrogen clouds would begin to contract, as predecessors of first stars (population III) and clusters of stars.

Even further in the past (redshift between 300 and 400) the sky would have been glowing red by what we now call cosmic microwave background.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.