The fact that the tortured light is genuinely from more distant galaxies and not part of the middle-ground galaxies is easily sorted out by looking at the "red shifts" of their light. This is the shifting of telltale element lines in the spectrum of light toward the red side of the rainbow. The higher the red shift, the further the object.
"People have used this technique to see galaxies 20 to 30 times fainter" than would otherwise be visible to current telescopes, Capak told Discovery News.
That means those rings and arcs are magnified light from galaxies that has taken more then 10 billion years to reach Earth. And if the sky is actually loaded with hundreds of thousands of these galactic lenses, there's a lot of information about early galaxies out there just waiting to be collected.
Another use for the gravitational lenses is in weighing the nearer galaxies that are doing the lensing. Since the lensing effect is caused by gravity, and gravity is directly related to matter, the effect is a great way to begin a genuine survey of large numbers of galaxies, explained Nick Scoville, head of the COSMOS project.
The COSMOS project combined data from the Hubble Space Telescope, Spitzer Space Telescope, XMM-Newton spacecraft, Chandra X-ray Observatory, Very Large Telescope, Subaru Telescope, and other observatories.
