2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/159300We study the singular homology (with field coefficients) of the moduli stack of stable n-pointed complex curves of genus g (the Deligne-Mumford compactification). Each of its irreducible boundary components determines via the Pontrjagin-Thom construction a map to a certain infinite loop space whose homology is well understood. We show that these maps are surjective on homology in a range of degrees proportional to the genus. This implies the existence of many new torsion classes in the homology of the moduli stack.30 pages, 3 figures - v2: expanded material on homotopy types of stacks, extended Pontrjagin-Thom construction to all local quotient stacks, added referencesAlgebraic TopologyAlgebraic Geometry32G15; 14H15; 22A22; 55R40text