Mars was once wet. Or was it dry? Different minerals tell different stories of the planet’s aquatic history. And those contradictions are among the results published in the journal Science today based on the observations of the Odyssey spacecraft. NASA’s Mars orbiter was launched in 2001 from Cape Canaveral. During its studies, Odyssey spotted the minerals hematite and olivine at different spots on Mars. One forms in the presence of water. The other quickly weathers away in water. There’s the dilemma.