Norman Harold Horowitz (March 19, 1915 – June 1, 2005) was a geneticist at Caltech who achieved national fame as the scientist who devised experiments to determine whether life might exist on Mars. His experiments were carried out by the Viking Lander of 1976, the first U.S. mission to successfully land an unmanned probe on the surface of Mars. Since 2013, Horowitz has been listed on the Advisory Council of the National Center for Science Education.