2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/126038We describe smooth projective horospherical varieties with Picard number 1. Moreover we prove that the automorphism group of any such variety acts with at most two orbits and we give a geometric characterisation of non-homogeneous ones.14 pagesAlgebraic Geometry14J45 14L30 14M17text