Telescope Research: Fermi Gamma-Ray Space Telescope

     The Fermi Gamma-ray Space Telescope was launched on June 11, 2008. It is a high-energy gamma-ray telescope that emits gamma-rays only in extreme conditions and it covers about 20% of the sky at all times, scanning continuously and covering the entire sky every three hours. The high-energy gamma-rays that Fermi emits cannot be refracted by a normal lens or mirror and instead are detected with technology used in high-energy particle accelerators. The emitted gamma-rays pass through a plastic anticoincidence detector and charged cosmic rays cause a flash of light which allows Fermi to detect the gamma-rays.
     From this point the detected gamma-rays then continue until they come in contact with an atom and produce an electron and a positron. The charged particles then create ions in thin silicon strip detectors which alternate in the X and Y directions allowing the particles’ progress to be tracked. Lastly, a cesium iodide calorimeter stops the particles and measures the energy deposited which allows physicists to estimate the energy and direction of the gamma-ray.
     Fermi was designed with three main missions in mind. The first was to explore environment out in the universe that are very different from Earth's environment. Secondly, it seeks to explore Dark Matter for other laws of physics and explain how black holes are able to accelerate objects to a speed almost as fast as the speed of light. And Lastly, Fermi was designed to understand gamma-ray bursts along with general longstanding questions. As far as discoveries to, Fermi was the first to detect gamma-rays from a nova which proved wrong the theory that novae are not able to emit radiation so high.