
There has been no definitive evidence of life’s existing on Mars to date. Early Viking experiments were inconsistent in their results, and the analyses of recent fossil evidence found in Mars meteorites cannot disprove the possibility of cross-contamination or of an explanation by a non-biological mechanism. We will conduct macroscopic and microscopic searches for evidence of life. Macroscopically, we will examine the atmosphere to look for biomarker gases and for compositional variations that would indicate active surface sources. Microscopically, we will conduct a spectroscopic examination of the surface and the immediate subsurface for signs of life. We also plan to conduct tests to identify the presence of biological chemical compounds, such as chlorophyll.