
IPFS News Link • Space Travel and Exploration
GRAVITATIONAL LENS SPLITS SUPERNOVA'S LIGHT 4 DIFFERENT WAYS
• http://www.popsci.com, By Loren GrushAbout 9.3 billion years ago, a supernova exploded in our universe. Since then, its light has been traveling the billions of light years it takes to get to our little planet we call home. But in between this supernova and Earth, there happens to be a massive galaxy, within a cluster of galaxies, which has had an interesting effect on the path of the light coming from this exploded star.
Using the Hubble Space Telescope, researchers from the University of California, Berkeley observed the galaxy's gravitational lensing effect on the supernova's light. Because the galaxy is so massive, it warps space-time around it, which bends the light as it travels to Earth. As a result, the galaxy creates four separate images of the supernova it its edges—a phenomenon called an Einstein's Cross.
Since four images arise, it means the supernova is almost exactly behind the galaxy in relation to us. When light from a distant object passes by an extremely massive object, the warped space-time changes the direction of the light, disrupting it from traveling in a straight line. A less-than-perfect alignment of these objects—which occurs most of the time—produces distortion like arcs and filaments. But as the Earth, the galaxy, and the supernova all lie in a line, the light's path is disrupted perfectly, making it appear in numerous distinct places around the galaxy.