Experts Looking at What Ended the Cosmic 'Dark Age'

A group of investigators is currently trying to determine whether the dark age of the Universe was brought to an end by the earliest stars, or by other space objects that we're currently unaware of. The study is tremendously important for our understanding of the Cosmos.

After the Big Bang exploded everything into being, the amorphous mass of material that was produced began to inflate and expand. However, what it did not contain was light in any form, as there were no sources available.

This is why the period of time spanning from the original event to the emergence of the first stars and dwarf galaxies is called the dark age. Things were literally dark in the Universe, as no photons were being produced.

But astrophysicists have recently identified a leakage of ionizing radiation, which they say comes from a very distant, very old dwarf galaxy. An international team of experts is now trying to figure out whether the first light that ever appeared originated in stars or some other objects.

According to data collected by the NASA Far Ultraviolet Spectroscopic Explorer (FUSE) satellite, it would appear that the dwarf galaxy was undergoing massive stellar formation at the time it released the radiation, Daily Galaxy reports.

When the Universe was in its earliest days, it was simply too hot to shine, the theory goes. Everything was clumped up together, and atoms were all ionized by the high temperatures. They slammed into each other like craze, breaking themselves up in their components.

But, 380,000 years after the Big Bang, the Cosmos cooled sufficiently to allow for atomic nuclei to catch on electrons again, and this led directly to the formation of electrically-neutral atoms.

Given that the result was a transparent gas, the original energy of the initial “explosion” was passed on to the Cosmic Microwave Background (CMB). In the new study, it was revealed that the formation of dwarf galaxies may have played a critical role in universal reionization.

“Although other groups have looked for this effect, this is the first solid detection of ionizing radiation escaping from a starburst region and into the intergalactic medium,” explains Nils Bergvall of the Astronomical Observatory in Uppsala, Sweden.

He and his group published the results of their findings in the latest issue of the European journal Astronomy and Astrophysics.