The thrill of exploring the unknown returns. Fill in the blank parts of our maps with monsters!
NASA’s Fermi Probes ‘Dragons’ of the Gamma-Ray Sky
One of the pleasures of perusing ancient maps is locating regions so poorly explored that mapmakers warned of dragons and sea monsters. Now, astronomers using NASA’s Fermi Gamma-ray Space Telescope find themselves in the same situation as cartographers of old. A new study of the ever-present fog of gamma rays from sources outside our galaxy shows that less than a third of the emission arises from what astronomers once considered the most likely suspects — black-hole-powered jets from active galaxies.
“Active galaxies can explain less than 30 percent of the extragalactic gamma-ray background Fermi sees,” said Marco Ajello, an astrophysicist at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), jointly located at SLAC National Accelerator Laboratory and Stanford University, Calif. “That leaves a lot of room for scientific discovery as we puzzle out what else may be responsible.”