The JUNO experiment, based in South of China, relies on the largest ~20ktons liquid scintillator detector ever built. Its physics programme encompasses the significant measurement of atmospheric mass-ordering using reactor neutrinos with a baseline of ~50km, the measurement of solar oscillation parameters to a sub-percent precision using, again, reactor neutrinos, as well as the high precision measurement of other natural neutrino sources such as geo-neutrinos, supernova neutrinos and maybe also solar and atmospheric neutrinos. Its size and technology would allow also leading sensitivity to proton-decay, specially exploring the kaon-channel. Technologically, JUNO is the most challenging LAND as it envisages the unprecedented control of the total calorimetry resolution of ≤3% at 1MeV. For this reason, a novel system of readout has been conceived and designed for unprecedented the control calorimetry systematics. In my seminar, I shall cover the general physics programme of JUNO making special emphasis to unique calorimetry control programme of the experiment, where the articulation of the novel "double-calorimetry” —  a system conceived, led and driven by IN2P3 scientists along with 20 laboratories world-wide with several important contributions to the scientific programme of JUNO.