Jewelry in space? Sort of ... but not exactly.
While this opal isn’t the sort of thing that would show up on a vintage necklace, pieces of the precious stone found in an Antarctic meteorite have more to tell us than any of Great-Grandma’s treasured heirlooms — never mind being much more antique.
Galactic opal has only ever been found in a meteorite once before. There have also been deposits on the surface of Mars that have contributed to the much-hyped hypothesis of primordial water and bacterial life on the Red Planet. Professor Hilary Downes of London’s Birkbeck College and her team of astronomers see the meteorite, which was once part of the shattered surface, or regolith, of a larger asteroid, as proof of water, and possibly life, in space. "This is more evidence that meteorites and asteroids can carry large amounts of water ice,” Downes explained. “Billions of years ago, they may have brought the water to the Earth and helped it become the world teeming with life that we live in today."
Opal rainbows reflect a surprising amount of water. H2O is absolutely mandatory in the Gaian (Earth-based) blueprints for life, which is why opal formation and composition backs the idea of asteroid ice being a catalyst for spawning the first microbial earthlings. October’s birthstone is also known by the slightly less glamorous molecular formula SiO2·nH2O. Those unearthly prisms come from a solution of silicon dioxide and water. This means that pendant you’re wearing is really a hydrated amorphous form of silica that may contain up to 30% water. It also means that wherever there are glints of a mineral (or non-crystalline mineraloid like opal) that needs water to form, there were also veins of water or ice.
Ice may be nothing special in Antarctica, but Downes’ evidence has revealed that the water responsible for forming the opal fragments came from anywhere but Earth. The NanoSIMS ion microprobe was able to prove that the isotopes (chemical variants of the same element) in the opal mirror the other minerals in EET 83309, as she her team have named their find, even though it did interact with Antarctic ice at some point.
We can’t be sure exactly where in the vast universe this ice came from. Asteroids are cosmic dust bunnies. They pick up different elements and minerals from their myriad adventures and encounters, which include being ravaged by solar storms and smashing into other asteroids. Meteorites carrying this evidence sometimes break off from asteroids and come hurtling down to earth. EET 83309 is a mashup of thousands of substances that crashed into something, probably another asteroid or even a moon, with liquid or frozen water on its surface.
It may mean extraterrestrial life...and it may not. The Gaian model has been our only scientific evidence for life since we’ve been blasting off satellites. For all we know there could be creatures out there that inhale methane and crunch on space rocks. While meteorites haven’t (yet) been able give us definite proof of aliens, EET 83309 has revealed a never-before-seen glimpse at the wonders floating through infinite space.
(Via Science Daily)