The LUNA experiment: past and future

The essential ingredients of nuclear astrophysics are the thermonuclear reac-tions which shape the life and death of stars and which are responsible for the synthesis of the chemical elements in the Universe. Deep underground in the Gran Sasso Laboratory the cross sections of the key reactions responsible for the hydrogen burning in stars have been measured with two accelerators of 50 and 400 kV voltage right down to the energies of astrophysical interest. In particular, the main results obtained during the 'solar' phase of LUNA are here reviewed and their influence on our understanding of the properties of the neutrino and of the Sun is discussed. Then, the future of LUNA during the next decade is outlined. It will be mainly focused on the study of the nuclear burning stages after hydrogen burning: helium and carbon burning. All this will be accomplished thanks to a new 3.5 MV accelerator able to deliver high current beams of proton, helium and carbon which will start running under Gran Sasso in 2019