Astrobiologist

Astrobiologists play a foundational role in shaping the scientific objectives of Mars missions, particularly in defining what we're actually looking for when we search for signs of life. NASA's Mars 2020 mission, which delivered the Perseverance rover to Jezero Crater, was designed with direct astrobiological input. Scientists in this field helped identify Jezero as a target precisely because it appears to be an ancient river delta — an environment on Earth consistently associated with preserved microbial biosignatures. Perseverance carries instruments like SHERLOC (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals), which uses ultraviolet Raman spectroscopy to detect organic compounds and minerals that could indicate past biological activity. Astrobiologists interpret the data flowing back from these instruments and help prioritize which rock samples are cached for eventual return to Earth under NASA's Mars Sample Return program, a joint effort with ESA currently in planning and development phases.

Beyond active rover missions, astrobiologists contribute critically to ESA's ExoMars program, specifically through the Rosalind Franklin rover, which carries a two-meter drill designed to access subsurface material shielded from Mars's harsh surface radiation. Astrobiologists advocated for this subsurface approach because ionizing radiation at the Martian surface destroys complex organic molecules within relatively short geological timescales, meaning any surviving biosignatures are more likely preserved underground. The rover's MOMA (Mars Organic Molecule Analyzer) instrument, which astrobiologists helped develop conceptually, uses gas chromatography and mass spectrometry to detect and characterize organic chemistry with extraordinary sensitivity. This kind of instrument design reflects years of astrobiology research into what chemical signatures life actually leaves behind, drawing on studies of extremophile organisms found in analog environments on Earth like the Atacama Desert, Antarctic dry valleys, and deep-sea hydrothermal vents.

Looking toward eventual human colonization, astrobiologists perform work that is both an enabler and a critical checkpoint. They are responsible for defining planetary protection protocols — the rigorous sterilization and contamination control standards enforced by NASA's Office of Planetary Protection — which govern how spacecraft are cleaned before launch to avoid introducing Earth microbes to Mars. This matters enormously for colonization planning because any future human presence will inevitably introduce biological contamination, and astrobiologists are working now to establish scientific baselines while the planet is still relatively pristine. They are also studying how Martian perchlorates, radiation levels, and thin atmosphere affect the survivability of terrestrial biology, research that directly informs habitat design, agriculture feasibility in sealed greenhouses, and the health risks future colonists will face. In essence, before humans can responsibly live on Mars, astrobiologists must first help humanity understand what life on Mars already means — or once meant.