The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kt liquid scintillator detector
equipped with 17612 20-inch PMTs as well as 25600 3-inch PMTs located 700 m underground
in southern China. It features a broad physics program with a primary goal of determining the
neutrino mass ordering to 3𝜎 in about 6 years. With an unprecedented energy resolution better than
3% at 1 MeV, it will measure the spectrum of antineutrinos emitted from two nuclear power plants
located 53 km from the detector. For the success of JUNO’s neutrino mass ordering determination
and its oscillation parameter precision measurement program, an accurate knowledge of the emitted
reactor neutrino spectrum is crucial. Therefore, a satellite detector with 2.8 tons of gadolinium-doped
liquid scintillator will be constructed in a distance of 30 m from one of the reactor cores
to provide a precise measurement of the unoscillated spectrum with an energy resolution better
than 2% at 1 MeV. This contribution will present studies on the sensitivity of the JUNO detector
to determine the neutrino mass ordering in combination with its satellite detector called TAO.