Welcome Letter To Church New Members

Friday, October 22, 2010

Welcome Letter To Church New Members

Solving the cosmic fog: The most distant galaxy far far " A team of European astronomers, using the ESO Very Large Telescope in northern Chile, has measured the distance to the remote galaxy known. Through careful analysis of the faint glow of the galaxy, they discovered that the light observed was emitted when the Universe was only 600 million years old (known as redshift of 8.6). These are the first confirmed observations of a galaxy whose light is clearing the opaque fog of hydrogen filling the universe at that early period. The results appear in the October 21 edition of the journal Nature

"Using the ESO Very Large Telescope have confirmed that a galaxy previously detected by Hubble, is the most distant object found so far in the Universe," says Matt Lehnert (Observatory Paris), author the paper reporting the results. "The power of the VLT and the SINFONI spectrograph allowed us to measure the distance to this very faint galaxy and discover that we are observing when the universe was less than 600 million years old."

Studying these early galaxies is extremely difficult. When we get to the Earth, its light, which initially was brilliant, they are very faint and small. This faint light is mainly located in the infrared part of spectrum because its wavelength is stretched product of the expansion of the universe, an effect known as redshift. To make things even more difficult, at this early stage -Less than a billion years after the Big Bang, the universe was not completely transparent and much of it was filled with a mist of hydrogen absorbed the intense ultraviolet light from young galaxies. The period during which the fog was still being cleared by this ultraviolet light is known as the era of reionization. Despite these challenges, the new Wide Field Camera 3 Hubble Space Telescope NASA / ESA in 2009 discovered several potent candidate objects that could be galaxies shining in the era of reionization. Confirm the distances of objects so faint and remote is a huge challenge and can only be achieved reliably using spectrographs based on very large telescopes on the ground, capable of measuring the redshift of the galaxy light. Matt Lehnert

continues the story: "After the announcement of the Hubble galaxy candidates did a quick calculation and we were excited to realize the immense light-gathering power of the VLT, combined with the sensitivity of the spectroscopic instrument SINFONI also a very long exposure time, may allow us to detect extremely weak brightness of these distant galaxies and measure their distance. "

special request to the Director General of ESO, the scientists obtained telescope time in the VLT and found a candidate galaxy-38135539 UDFy call for 16 hours. After two months of very careful analysis and review of the results, the team concluded that had clearly detected a very weak hydrogen emission with a redshift of 8.6, which makes this galaxy the most distant object so far confirmed spectroscopy. A redshift of 8.6 corresponds to a spiral galaxy only 600 million years after the Big Bang.

The co-author Nicole Nesvadba (Institut d'Astrophysique Spatiale) summarizes this work: "Measuring the redshift of the most distant galaxy found so far is very exciting in itself, but the astrophysical implications of this detection are even more important. This is the first time we know for sure that we are looking at one of the galaxies that cleared the fog that filled the early universe. "

One of the amazing things about this discovery is that the brightness of UDFy-38135539 does not seem to be strong enough by itself to clear the fog of hydrogen. "There must be other galaxies, probably weaker and less massive, close companion UDFy-38135539, which also helped to make transparent the space around the galaxy. Without this extra help, the light from the galaxy, no matter how brilliant it would have been trapped in the fog surrounding hydrogen and we would not have been able to detect it, "says co-author Mark Swinbank (Durham University).

The co-author Jean-Gabriel Cuby (Laboratoire d'Astrophysique de Marseille) said: "Studying the era of reionization and galaxy formation is to push the technical limits of the telescopes and instruments, but this is just the kind of science that will be routine when

European Extremely Large Telescope of ESO - which is the optical and infrared telescope, the world's largest, is operating. "

Original Date: October 18, 2010 Original Link