Spacecraft aims to expose violent hearts of galaxies

摘要

Who would have thought that a ringside seat at some of the Universes most extreme events could come cheap? But by the standards of space-based astronomy, the NuSTAR telescope that NASA plans to launch as early as this month has a modest budget, US$165 million. Yet it will be sensitive to the high-energy photons produced at the turbulent thresholds of supermassive black holes. Due to be lofted into orbit by a Pegasus rocket launched in mid-air from a carrier jet, NuSTAR (Nuclear Spectroscopic Telescope Array) is taking aim at an under-explored region of the spectrum. It will detect 'hard' X-rays at 5-80 kiloelectronvolts, an energy range between the softer, lower-energy X-rays probed by telescopes such as the Chandra X-ray Observatory and the γ-rays measured by satellites such as the Fermi telescope.