Subtitles section Play video Print subtitles Only six hundred million years after the big bang, the universe was in a fog. this is what the universe looked like before any galaxies had formed Here, there are no luminous objects no stars and certainly no galaxies When the universe cooled down after the Big Bang electrons and protons combined to form neutral hydrogen gas At this time in our history no photons could pass through the universe was opaque. This dark age ended when the first stars formed and their intense ultraviolet radiation pierced the veil by splitting the hydrogen atoms back into electrons and protons In this simulation the dark areas are opaque, the blue areas translucent. The fog lifted when stars were born. These hot young stars blew away the cosmic fog of hydrogen gas with ultraviolet radiation and these stars formed into the very first galaxies. clearing the way for their photons to begin their too long, arduous journey across creation. The first galaxies ever to form, lifed the universal fog forever. The era for reionization had begun. On October 19th 2010, astronomers announced a measurement of one of the first galaxies ever to form in the universe, and it formed during this period. Sensitive instruments on the European Southern Observatory's Very Large Telescope recorded a spectrum of a galaxy first imaged by the Hubble Space Telescope in January, 2010 Starting with a new Ultra Deep Field image taken in January, 2010, with the upgraded Wide Field Camera 3 sensitive to the infrared astronomers looked at every faint galaxy within it these faint galaxies were among the first in existence. From these faint smudges, candidates for further study with the ESO SINFONI spectrograph were selected. These galaxies were so faint, it wasn't at all clear if a spectrum could be obtained. Lying in a very obscure region of the Ultra Deep Field the ESO astronomers pointed the Very Large Telescope spectrograph at one of the faintest objects they could see in the image. Early in time, this galaxy was once exceedingly bright in the ultraviolet, but by the time it's light traversed the observable universe to land on our detectors, its photons had been diminished to a faint, red glow. The feeble red light from this galaxy was collected for over sixteen long hours resulting in a spectrum with a measured redshift of 8.6 This galaxy was alive 13.1 billion years ago when the cosmos was still in its infancy, and its redshift is the largest ever recorded anywhere in the universe. Looking at galaxies this remote is very difficult, but they're crucial to our understanding of how galaxies came into existence This observation of a galaxy early in the lifetime of the universe of came as a surprise Galaxies, it seems, have existed much earlier than was previously thought. This distant galaxy not only helped clear the early hydrogen fog blanketing the universe, it is now also helping to clear the fog of ignorance in our understanding of the earliest period of existence.
B2 galaxy fog universe faint hydrogen ultraviolet The Most Distant Galaxy Ever Measured 23 3 Wonderful posted on 2014/04/17 More Share Save Report Video vocabulary