Mars is generally regarded as a place that can't support life, but new research sheds light on how the Red Planet evolved into the barren, inhospitable world we see today.
gizmodo.com
NASA’s Curiosity rover has added a new wrinkle to the theory that the surface of Mars was once hospitable to alien life. New chemical analysis of Martian dirt hints at eras in the planet’s past where the conditions necessary for life may have been met, but only for relatively short periods of time. The very processes that led to elements vital to life being present in Martian soil, may also have led to the waterless conditions currently present.
The trundling robot, which has been exploring Mars’ Gale Crater since 2012, analyzed soil and rock samples from the planet’s surface as part of an effort to find carbon-rich minerals. Carbon is often seen as being vital to life, as its ability to form strong bonds with a host of other atoms makes molecules like DNA and RNA possible. What the rover found suggests that Mars is not only a hostile environment today, but that any periods when the planet could have been habitable may have been brief. However, as the saying goes, life finds a way. More research is needed to determine if microbes might have thrived in more hospitable conditions underground.
NASA’s rovers have found evidence that
Mars once had lots of organic compounds rich in the
carbon-bearing minerals known as carbonates, and a meteorite with Martian origins has been
found to contain carbon, as well. To figure out which isotopes of carbon and oxygen are present in those carbonates, the Curiosity team turned to the rover’s Sample Analysis at Mars instruments. The equipment heats collected samples to over 1,650 degrees Fahrenheit (899 Celsius) and then uses a laser spectrometer to analyze the gasses that are produced.
When the data was transmitted back to Earth, NASA scientists determined it contained higher levels of certain heavy carbon and oxygen isotopes than had previously been found in Martian samples.
Both elements are vital to the carbon cycle, in which carbon goes through different forms, thanks to processes such as photosynthesis. The carbon cycle is an integral part of life here on Earth, but the researchers found the proportion of heavier isotopes of carbon and oxygen in the samples was far higher than what’s found on Earth.