One measure of its rarity is its astonishing value one 102g sample of the same rock is on sale for $100,000 . To ensure that it was genuine, I enlisted the help of Prof Pillingers colleagues. Andy Tindle studied a slide of NWA2975 provided by Ted Bunch of Northern Arizona University, a member of the team who originally described the meteorite in 2005. This revealed a mixture of rounded desert sand grains and various minerals of the kind found on Mars, such as pyroxene, which contains manganese and iron in a ratio typical of the Red Planet.
To make absolutely sure, Richard Greenwood and Jenny Gibson removed around ten-thousandths of a gram for further analysis. Using an instrument called a mass spectrometer , they studied the relative abundance in the meteorites silicate minerals of three isotopes of oxygen oxygen-16, oxygen-17 and oxygen-18. They were released for analysis with the help of a laser and a powerful reagent.
Because the relative abundance of these isotopes varies throughout the solar system, it is possible to use them like a DNA test in order to identify whether a meteorite comes from the Moon, an asteroid or Mars. In this case, they found a slight excess in the abundance of oxygen-17 and oxygen-18 compared with rocks from Earth, just as we would expect from a Martian rock.
What this tells us is that we dont have to go to Mars to get all kinds of insights into the Red Planet. We can reveal a lot simply by studying its meteorites to reveal data from the composition of the atmosphere to the presence of water. And, of course, these meteorites offer us a welcome opportunity to search for life signs, as we wait for the
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