Cosmic dawn ended 200 million years later than cosmologists thought

There is a person by the name ofLeah Crane.

Cosmic dawn is now known. The universe was dark for about 100 million years after the big bang. Stars and galaxies began to form, emitting light and ionising the hydrogen gas in a process called reionisation, or Cosmic Dawn. All of the hydrogen was ionised after the big bang.

The Very Large Telescope in Chile and the W. M. Keck Observatory in Hawaii were used to calculate this date. The quasars must have formed within a billion years of the big bang.

The light from the quasars was absorbed by neutral hydrogen and ionised hydrogen. When the light stopped traveling through neutral hydrogen, it encountered only ionised hydrogen in the space between the galaxies.

Read more: Mystery of the cosmic dawn: What’s eating the first starlight?

The structure of reionisation is similar to a bubble. When the hydrogen gas is ionised across the sky at the locations of all of the quasars, reionisation is completed. When all the quasars agree, it is the end of reionization.

The date they found is 200 million years later than they had thought. The first generation of stars may be easier to observe than thought.

The history of the universe has gone through many phases between the big bang and now. The next step is to link the reionisation information to the galaxies that are causing the gas to be destroyed.

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