Antarctic meteorite contains opal, provides clues about formation of life on Earth

By @ritwikroy1985 on
Antarctica
Natural-color sea ice off the coast of East Antarctica's Princess Astrid Coast is seen in this picture from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite acquired April 5, 2015 and released April 8, 2015. Reuters/NASA/Jeff Schmaltz/LANCE/EOSDIS Rapid Response

Scientists have discovered pieces of opal in a meteorite in Antarctica. The findings are extremely important for related studies on water and its life-forming abilities. Opals are beautiful gemstones and according to the team of British researchers, the opal-studded meteorite is offering new clues as to the origins of life on Earth. Opals are associated with water and their structure contains up to 30 percent of the precious, life-giving substance.

The findings of the study demonstrate that meteorites delivered water ice to asteroids early in our Solar System’s history. Led by professor Hillary Downes of Birkbeck College in London, teh findings of the study were announced at the National Astronomy Meeting in Nottingham on Monday 27 June.

Opal has not been discovered on surface of any asteroid before. It was found on a meteorite only once before. The new meteorite, named EET 83309, was closely analysed by Downes and her team. They found that it had pieces of different meteorites embedded within it, suggesting that its parent asteroid was pummelled by other rocks. One of these collisions may have introduced water ice to the asteroid that led to the formation of the opal.

“The pieces of opal we have found are either broken fragments or they are replacing other minerals. Our evidence shows that the opal formed before the meteorite was blasted off from the surface of the parent asteroid and sent into space, eventually to land on Earth in Antarctica,” Downes said in a Royal Astronomical Society statement.

The team of scientists used various techniques to analyse the opal and check its composition. They have enough evidence that the opal is extra-terrestrial in origin and did not form when the meteorite was already in the Antarctic ice. Using Open University’s NanoSims instrument, the scientists were able to clearly see that even though the opal interacted with Antarctic waters to some extent, the isotopes matched the other minerals in the original meteorite.

This is more evidence that meteorites and asteroids can carry large amounts of water ice. Although we rightly worry about the consequences of the impact of large asteroid, 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,” Downes added.