NUSES is a space mission scheduled for launch in late 2026 into a Sun-synchronous Low Earth Orbit at 550 km altitude. During its three-year nominal lifetime the satellite will test innovative methods for observing low-energy cosmic and gamma rays, astrophysical neutrinos, and for monitoring space-weather phenomena and lithosphere-atmosphere-ionosphere-magnetosphere couplings. Two complementary payloads are on board: Terzina, an optical Cherenkov telescope for extensive air showers, and Zire, a particle detector covering an energy range from a few MeV up to hundreds. To extend Zire's sensitivity to lower energies, the Low-Energy Module (LEM) has been developed. The LEM is a compact (10 x 10 x 10 cm(3)) particle spectrometer capable of measuring electrons from 0.1 to 7 MeV and protons from 3 to 50 MeV along the satellite orbit. A drilled plastic scintillator acts as an active collimator, vetoing off-axis tracks, while five silicon spectrometers, completed by a plastic calorimeter and lateral veto, provide event-by-event identification. This layout yields an angular resolution of about for protons and an electron threshold below 30 keV, enabling operations in high-radiation regions such as the South Atlantic Anomaly and the inner Van Allen belt. By tracking variations in trapped-particle fluxes the LEM will investigate precipitation episodes linked to geomagnetic storms, solar flares, thunderstorms, and possible seismic precursors, thus contributing both to space-weather forecasting and to the validation of particle-acceleration and models of Magnetospheric-Ionospheric-Lithospheric Coupling. Preliminary simulations and laboratory tests confirm the feasibility of the design and its expected performance. (c) 2025 The Authors. Published by Elsevier B.V. on behalf of COSPAR. This is an open access article under the CC BY license(http://creativecommons.org/licenses/by/4.0/).