In June, NASA’s Curiosity rover found new evidence preserved in rocks on Mars that suggests the planet could have supported ancient life, as well as new evidence in the Martian atmosphere that relates to the search for current life on the Red Planet. While not necessarily evidence of life itself, these findings are a good sign for future missions exploring the planet’s surface and subsurface.
Researchers reexamined the original, microfilm preserved, Viking gas chromatograph‐mass spectrometer data sets. They found evidence for the presence of chlorobenzene in Viking Lander 2 (VL‐2) data at levels corresponding to 0.08–1.0 ppb (relative to sample mass), in runs when the sample was heated to 350°C and 500°C. Additionally, we found a correlation between the temperature dependence of the chlorobenzene signal and the dichloromethane signal originally identified by the Viking gas chromatograph‐mass spectrometer team. They considered possible sources of carbon that may have produced the chlorobenzene signal, by reaction with perchlorate during pyrolysis, including organic carbon indigenous to the martian parent sample and instrument contamination. They conclude that the chlorobenzene signal measured by VL‐2 originated from martian chlorine sources. They show how the carbon source could originate from the martian parent sample, though a carbon source contributed from instrument background cannot yet be ruled out.
Complex Organics Bubble up from Ocean-world Enceladus
Data from NASA’s Cassini spacecraft reveal complex organic molecules originating from Saturn’s icy moon Enceladus, strengthening the idea that this ocean world hosts conditions suitable for life. Research results show much larger, heavier molecules than ever before.
Powerful hydrothermal vents mix up material from the moon’s water-filled, porous core with water from the moon’s massive subsurface ocean – and it is released into space, in the form of water vapor and ice grains. A team led by Frank Postberg and Nozair Khawaja of the University of Heidelberg, Germany, continues to examine the makeup of the ejected ice and has recently identified fragments of large, complex organic molecules.
Previously, Cassini had detected small, relatively common organic molecules at Enceladus that were much smaller. Complex molecules comprising hundreds of atoms are rare beyond Earth. The presence of the large complex molecules, along with liquid water and hydrothermal activity, bolsters the hypothesis that the ocean of Enceladus may be a habitable environment for life.
Titan
Titan has lakes of hydrocarbons on its surface.
Titan is the only known moon with a significant atmosphere, and its atmosphere is the only nitrogen-rich dense atmosphere in the Solar System aside from Earth’s.
