GERMAN SCIENCE WEEKLY HIGHLIGHT - 5

Those two pictures are of the same piece of the sky.   (You can click on the mangnifying glass to see it bigger.)  The bottom one seems crisper and clearer, and indeed it's a beautiful and special picture.  But the top one is something quite revolutionary: it's from the new gamma ray telescope called HESS in the Namibian desert, the telescope that can "see" the highest frequency radiation in the world.

There's lots of kinds of electromagnetic radiation.  You can see some of it with your own eye, but that light falls within a very thin range of frequency.  This diagram shows how little of the radiation you can actually see. Bildunterschrift:

The waves of radiation that HESS detects are at the high end of the chart.  They're called gamma rays; radioactive substances produce them too.  Gamma rays can tell us a lot about the deepest reaches of the universe; but first, Dr. Stefan Gillesen of the Max-Planck Institute for Nuclear Physics, who has been working with HESS, will tell us what we're seeing in the bottom photo, and how it compares with the top.