A new paper presents an analysis of mixing ratios in thirty comets with respect to H2O. The research identified trends when comparing the mixing ratios of individual comets to average mixing ratios across the population studied. For instance, Jupiter-family comets were found to be depleted in volatile species (with respect to H2O) when compared to long-period Oort cloud comets. Astrobiologists are interested in the composition of comets because these objects from space may have delivered key components for the origin of life to the early Earth.

The study, “Emerging trends and a comet taxonomy based on the volatile chemistry measured in thirty comets with high-resolution infrared spectroscopy between 1997 and 2013,” was published in the journal Icarus. The research was funded through NASA’s Emerging Worlds program, which supports some projects that investigate science goals of relevance to the NASA Astrobiology Program.