The Fermi Paradox is the unexpected silence of the cosmos under the Assumption of Mediocrity, in a cosmos known to have abundant planets and life precursor chemicals. On Mars, the nearest Earthlike planet in the cosmos, the concentration of 129Xe in the Martian atmosphere, the evidence from 80Kr abundance of intense 1014/cm2 flux over the Northern young part of Mars, and the detected pattern of excess abundance of Uranium and Thorium on Mars surface, relative to Mars meteorites, can be explained as due to two large thermonuclear explosions on Mars in the past. Based on the pattern of thorium and radioactive potassium gamma radiation, the explosions were centered in the Northern plains in Mare Acidalium at approximately 50N, 30W,near Cydonia Mensa and in Utopia Planum at approximately 50N 120W near Galaxias Chaos, both locations of possible archeological artifacts. The xenon isotope mass spectrum of the Mars atmosphere matches that from open air nuclear testing on Earth and is characteristic of fast neutron fission rather than that produced by a moderated nuclear reactor. The high abundance of 40Ar cannot be explained by mass fractionation during atmospheric loss, and must be the result of neutron capture on 39K, also requiring an intense neutron flux on the Mars surface as is the high abundance of 17N and deuterium. Modeling the 129Xe component in the Mars atmosphere as due to fast neutron fission and the 80Kr as due to delayed neutrons from a planetwide debris layer, and assuming an explosive disassembly of uranium-thorium casing into a planet wide debris layer with 10% residue, all three estimates arrive at approximately 10 25 J, or a yield of 10 10 Megatons. This is similar to the Chicxulub event on Earth and would be large enough to create a global catastrophe and change Mars global climate. The absence of craters at the site suggests centers of the explosions where above the ground. The explosions appear due to very large fusion-fission devices of similar design as seen on Earth, and the Acidalia device, the largest, being approximately 80meter radius. The explosions appear correlated with two sites of possible archeology, sites which formed the basis for the Cydonian Hypothesis. The Cydonian Hypothesis is therefore reconsidered in the light of new imaging and geochemical data. A model of Earthlike eroded archeology is adopted for comparison with Mars artifacts using the pyramids at Giza and the Sphinx and Olmec heads as analogs under the Principle of Mediocrity with attention to details. The new images of the Face at Cydonia Mensa confirm eyes, nose, mouth, helmet structure with additional detail of nostrils and helmet ornaments being clearly seen in new images with details at approximately 1/10 scale of the face. New imagery confirms the pyramid structure seen in Viking images of the The D&M pyramid and new high resolution images show evidence of collapsed brickwork. New images of a face found at Galaxias Chaos (the Utopia site) confirms facial structure with eyes, nose, mouth and helmet. High resolution imagery shows symmetric brickwork around the nose region. The civilization appears to have been primitive and indigenous to Mars. Taken together, the evidence suggests that Mars was the locale of a planetary nuclear massacre. The answer to Fermi's Paradox may thus lie on Mars. It is recommended that a mission for human occupation of Mars be immediately initiated to maximize knowledge of what transpired there.