From “Ancient 13-Billion-Year-Old Galaxies Observed by VLT ‘Time Machine’” (The Daily Galaxy October 17, 2011), we learn,
An international team of astronomers used the VLT as a time machine, to look back into the early Universe and observe several of the most distant galaxies ever detected. They have been able to measure their distances accurately and find that we are seeing them as they were between 780 million and a billion years after the Big Bang.
The Very Large Telescope (VLT) is the flagship for European ground-based astronomy made up of four separate optical telescopes organized in an array formation, built and operated by the European Southern Observatory (ESO) at the Paranal Observatory on Cerro Paranal, a 2,635 m high mountain in the Atacama Desert in northern Chile.
“We see a dramatic difference in the amount of ultraviolet light that was blocked between the earliest and latest galaxies in our sample,” says lead author Laura Pentericci of INAF Rome Astronomical Observatory. “When the Universe was only 780 million years old this neutral hydrogen was quite abundant, filling from 10 to 50% of the Universe’ volume. But only 200 million years later the amount of neutral hydrogen had dropped to a very low level, similar to what we see today. It seems that reionisation must have happened quicker than astronomers previously thought.”