At first, right after the Big Bang, the universe was too hot for nuclei and electrons to combine into the kinds of neutral atoms that are familiar to us today. How soon after the beginning did it become cool enough for neutral atoms to form?

Question

Quizplus · Accepted Answer

It took a few hundred thousand years after the beginning for the universe to become cool enough for neutral atoms to form. This is known as recombination and is the point at which the cosmic microwave background radiation was released. Choice A is incorrect because it is an exaggerated time frame for recombination to occur. Choice B is also incorrect as it is too soon after the Big Bang. Choice D is incorrect because it is much later than the actual time for recombination. Choice E is a humorous option and does not provide a scientific answer.

At First, Right After the Big Bang, the Universe Was