![]() Interstellar dust is also found in comets and meteorites that have not been heated up for a prolonged period in their history,” adds Kramers. “Even more unusual, the matrix contains a high amount of very specific carbon compounds, called polyaromatic hydrocarbons, or PAH, a major component of interstellar dust, which existed even before our solar system was formed. But Hypatia’s matrix has a massive amount of carbon and an unusually small amount of silicon.” “In chondritic meteorites, we expect to see a small amount of carbon and a good amount of silicon (Si). “If it were possible to grind up the entire planet Earth to dust in a huge mortar and pestle, we would get dust with on average a similar chemical composition as chondritic meteorites,” says Kramers. Straight away, the Hypatia mineral matrix (represented by fruitcake dough), looks nothing like that of any known meteorites, the rocks that fall from space onto Earth every now and then. The original extraterrestrial rock that fell to Earth must have been at least several meters in diameter, but disintegrated into small fragments of which the Hypatia stone is one. And the flour dusting the cracks of the fallen cake represent the ‘secondary materials’ we found in the fractures in Hypatia, which are from Earth,” he says. The glace cherries and nuts in the cake represent the mineral grains found in Hypatia ‘inclusions’. “We can think of the badly mixed dough of a fruit cake representing the bulk of the Hypatia pebble, what we called two mixed ‘matrices’ in geology terms. The internal structure of the Hypatia pebble is somewhat like a fruitcake that has fallen off a shelf into some flour and cracked on impact, says Prof Jan Kramers, lead researcher of the study published in Geochimica et Cosmochimica Acta on. However, if the pebble was not from Earth, what was its origin and could the minerals in it provide clues on where it came from? Micro-mineral analyses of the pebble by the original research team at the University of Johannesburg have now provided unsettling answers that spiral away from conventional views of the material our solar system was formed from. (The stone was named Hypatia after Hypatia of Alexandria, the first Western woman mathematician and astronomer). If you found your rock in a desert environment, consider whether its black surface might be desert varnish.In 2013, researchers announced that a pebble found in south-west Egypt, was definitely not from Earth.īy 2015, other research teams had announced that the ‘Hypatia’ stone was not part of any known types of meteorite or comet, based on noble gas and nuclear probe analyses. Rocks in the desert will sometimes develop a shiny black exterior that looks similar to fusion crust. ![]() ![]() The fusion crust may look like a black eggshell coating the rock.If your rock does not have a fusion crust, it is most likely not a meteorite.A fusion crust will most likely be smooth and featureless, though it may also include ripple marks and “droplets” where molten stone had moved and resolidified.government agency responsible for conducting scientific research on the nation's land, natural resources, and natural disasters Go to source If your rock’s surface looks like it has melted and shifted, it may be a meteorite. As rocks pass through the Earth’s atmosphere, their surfaces begin to melt and air pressure forces the molten material back, leaving a featureless, melt-like surface called a fusion crust. Determine whether the rock has a fusion crust. ![]()
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