A golden age for astronomy

For some decades, astrophysics has undergone a technological and conceptual revolution. Thanks to new and powerful observational facilities, on the ground and in space, every stage of evolution of the Universe and its components is now within reach. A new era has started, ten years ago, with the discovery of planets around stars other than the sun, officially launching the quest for other worlds. The presence of a black hole in the center of our galaxy is now established, from its gravitational effect on stars orbiting around it; we can study details of the way black holes accrete matter, and use them to test General Relativity. A wealth of diverse observations find the best interpretation within the Big Bang cosmology, with a Universe totally dominated by dark energy, a form of Einstein's cosmological constant, and by dark matter of unknown nature.