Elemental discovery points to history of water on Mars
19 Dec 2016 by qwwqdccwwm.d qwwqdccwwm.d
Boron has been detected for the first time on planet Mars, indicating the presence of long-term groundwater in the past.
Boron has been detected for the first time on planet Mars, indicating the presence of long-term groundwater in the past.
Discovered by NASA’s Curiosity rover, boron is associated with arid sites where water has evaporated away. The rover is exploring the Gale Crater on Mars, an area NASA believes to have had lakes in the past.
Patrick Gasda, a postdoctoral researcher at Los Almos National Laboratory, said: “No prior mission to Mars has found boron. If the boron we found in calcium sulphate mineral veins on Mars is similar to what we see on Earth, it would indicate that the groundwater of ancient Mars that formed these veins would have been 0-60°C and neutral-to-alkaline pH.”
When a lake in Gale crater dried out it left behind boron in an overlying layer that the rover has not reached yet and scientists have theorised two different reasons for the presence of boron. They think either some of the material was carried out by groundwater into fractures in the rocks or perhaps chemistry changes in clay deposits and groundwater affected how where boron was deposited.
As Curiosity explores different areas of the crater, moving uphill, the composition changes, becoming more clay and boron rich. This can provide scientists with information about initial sediment deposits and how groundwater either altered or moved sediments.
Professor John Grotzinger, from Caltech, in California, said: “There is so much variability in the composition at different elevations, we've hit a jackpot. A sedimentary basin such as this is a chemical reactor. Elements get rearranged. New minerals form and old ones dissolve. Electrons get redistributed. On Earth, these reactions support life."
The rover was able to make these measurements using a Chemistry and Camera (Chemcam) Instrument, developed at Los Alamos alongside the French space agency. It fires a laser at Martian rock and soil, analysing the vaporised materials.
This finding, alongside several others, was presented at the American Geophysical Union conference in San Francisco in December.
