2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/104241Stable lumps of quark matter may be present in cosmic rays at a flux level, which can be detected by high precision cosmic ray experiments sensitive to anomalous "nuclei" with high mass-to-charge ratio. The properties of these lumps, called strangelets, are described, and so is the production and propagation of strangelets in cosmic rays. Two experiments underway which are sensitive to a strangelet flux in the predicted range are briefly described. Finally it is summarized how strangelets circumvent the acceleration problem encountered by conventional candidates for ultra-high energy cosmic rays and move the Greisen-Zatsepin-Kuzmin cutoff to energies well above the observed maximum energies.16 pages, 29th Johns Hopkins Workshop on current problems in particle theory: Strong Matter in the HeavensAstrophysicsHigh Energy Physics - PhenomenologyNuclear Theorytext