A Telescope Bigger than a Galaxy   
       
   March 7, 2014:  More than 400 years ago, Galileo turned a primitive spyglass   
   toward the sky, and in just a few nights learned more about the unseen heavens   
   than all of the scientists and philosophers before him, combined.   
       
   Since then astronomers have been guided by a simple imperative: Make Bigger   
   Telescopes. As the 21st century unfolds, the power of optics has grown a   
   million-fold.  Telescopes cap the highest mountains, sprawl across deserts,   
   fill valleys and even fly through space. These modern giants provide   
   crystal-clear views of stars and galaxies billions of light years farther away   
   than anything Galileo ever saw, each breakthrough in size bringing a new and   
   deeper understanding of the cosmos.   
       
   It makes you wonder, how big can a telescope get?   
       
   https://www.youtube.com/watch?v=3_iTofcXqfM   
       
   A new ScienceCast video peers through the biggest telescope in the history of   
   astronomy.  Play it!   
       
   Would you believe, bigger than an entire galaxy? At the January 2014 meeting   
   of the American Astronomical Society, researchers revealed a patch of sky seen   
   through a lens more than 500,000 light years wide.   
       
   The "lens" is actually a massive cluster of galaxies known as Abell 2744. As   
   predicted by Einstein's Theory of General Relativity, the mass of the cluster   
   warps the fabric of space around it.  Starlight passing by is bent and   
   magnified, much like an ordinary lens except on a vastly larger scale.   
       
   Lately, the Hubble Space Telescope, along with the Spitzer Space Telescope and   
   the Chandra X-ray Observatory, has been looking through this gravitational   
   lens as part of a program called "Frontier Fields."   
       
   "Frontier Fields is an experiment to explore the first billion years of the   
   Universe's history," says Matt Mountain from the Space Telescope Science   
   Institute in Baltimore, Maryland. The question is, "Can we use Hubble's   
   exquisite image quality and Einstein's theory of general relativity to search   
   for the first galaxies?"   
       
   The answer seems to be "yes."  At the AAS meeting, an international team led   
   by astronomers from the Instituto de Astrof¡sica de Canarias and La Laguna   
   University discussed Hubble and Spitzer observations of the Abell 2744   
   cluster. Among the results was the discovery of one of the most distant   
   galaxies ever seen-a star system 30 times smaller yet 10 times more active   
   than our own Milky Way.  Bursting with newborn stars, the firebrand is giving   
   astronomers a rare glimpse of a galaxy born not long after the Big Bang itself.   
       
   Overall, the Hubble exposure of Abell2744 revealed almost 3,000 distant   
   galaxies magnified as much as 10 to 20 times larger than they would normally   
   appear. Without the boost of gravitational lensing, almost all of those   
   background galaxies would be invisible.   
       
   Abell 2744 is just the beginning.  Frontier Fields is targeting six galaxy   
   clusters as gravitational lenses. Together, they form an array of mighty   
   telescopes capable of probing the heavens as never before.   
       
   For more news from Frontier Fields visit frontierfields.org   
       
   Credits:   
   Author: Dr. Tony Phillips | Production editor: Dr. Tony Phillips | Credit:   
   Science@NASA   
       
       
   Regards,   
       
   Roger   
      
   --- D'Bridge 3.99   
    * Origin: NCS BBS - Houma, LoUiSiAna (1:3828/7)