2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/123289The Pioneer 10/11 missions, launched in 1972 and 1973, and their navigation are reviewed. Beginning in about 1980 an unmodeled force of ~ 8 x 10^{-8} cm/s^2 appeared in the tracking data, it later being verified. The cause remains unknown, although radiant heat remains a likely origin. A set of efforts to find the solution are underway: a) analyzing in detail all available data, b) using data from the New Horizons mission, and c) considering an ESA dedicated mission.12 pages, 7 figuresGeneral Relativity and Quantum Cosmologytext