A decades-long quest for incontrovertible and complex Martian organics — the chemical building blocks of life — is over.
After almost six years of searching, drilling and analyzing on Mars, the Curiosity rover team has conclusively detected three types of naturally-occurring organics that had not been identified before on the planet.
The Mars organics Science paper, by NASA’s Jennifer Eigenbrode and much of the rover’s Sample Analysis on Mars (SAM) instrument team, was twinned with another paper describing the discovery of a seasonal pattern to the release of the simple organic gas methane on Mars.
This finding is also a major step forward not only because it provides ground truth for the difficult question of whether significant amounts of methane are in the Martian atmosphere, but equally important it determines that methane concentrations appear to change with the seasons. The implications of that seasonality are intriguing, to say the least.
In an accompanying opinion piece in Science, Inges Loes ten Kate of Utrecht University in Netherlands wrote of the two papers: “Both these findings are breakthroughs in astrobiology.”
The clear conclusion of these (and other) recent findings is that Mars is not a “dead” planet where little ever changes. Rather, it’s one with cycles that appear to produce not only methane but also sporadic surface water and changing dune formations.
Finding organic compounds on Mars has been a prime goal of the Curiosity rover mission.
Those carbon-based compounds surely fall from the sky on Mars, as they do on Earth and everywhere else, but identifying them has proven illusive.
The consequences of that non-discovery have been significant. Going back to the Viking missions of 1976, scientists concluded that life was not possible on Mars because there were no organics, or none that were detected.
But the reasons for the disappearing organics are pretty well understood. Without much of an atmosphere to protect it, the Martian surface is bombarded with ultraviolet radiation, which can destroy organic compounds. … Read more