Mapping the X-ray Sky with SRG: First Results from eROSITA and ART-XC

In little more than half a century, X-ray astronomy has established itself as a fundamental domain of observational astrophysics. X-rays probe the hot and energetic components of the Universe, encompassing, among others, the million degree coronae of stars, the remnants of supernovae, the ultra-dense matter in neutron stars, the immediate surroundings of black holes, the plasma filling galaxy clusters – the most massive objects in the Universe. Successfully launched in July 2019, after more than a decade of development, the Russian-German Spectrum-RG (SRG) mission will contribute to the X-ray exploration of the Universe by performing eight all-sky surveys, each lasting half a year, with its two scientific instruments: eROSITA, the German-built telescope array operating between ~0.3-8 keV, and ART-XC, the Russian-built hard-X-ray focusing telescope array, operating between ~3-30 keV.