Author Question: A moment before, you were enveloped in a bright plasma. You could not see very far as free electrons ... (Read 62 times)

nenivikky · **on:** Jul 27, 2018

A moment before, you were enveloped in a bright plasma. You could not see very far as free electrons zipped around your head, scattering photons. But now, the universe has suddenly become transparent and you can see clearly.

There seem to be no planets or stars, only a gas filled with mostly neutral hydrogen atoms. Where are you?
A) You are in the universe about 5 minutes after the Big Bang just as the nucleosynthesis era is ending.
B) You are in intergalactic space within a rich cluster of galaxies.
C) You are in the universe when it was about 500 million years old, just before galaxies began to form.
D) You are in the universe about 380,000 year after the Big Bang during the formation of the cosmic background radiation.
E) You are in a closed universe just as it begins to re-collapse.

Question 2

X-rays, because they have more energy, travel through space faster than visible light.

Indicate whether the statement is true or false