The essential ingredients of nuclear astrophysics are the thermonuclear reactions which are responsible for the production of most of the energy radiated by stars and for the genesis 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.
At first, the main results obtained during the 'solar' phase of LUNA are briefly reviewed. Then, the current 'isotope' phase is described together with the main astrophysical consequences.
Finally, 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.