Wednesday, 21 August 2019

Meteorite found by gold prospector - The first found in Victoria since 1995 - Comes to Museums Victoria

The Maryborough Meteorite
A 17kg stony meteorite found by chance by a gold prospector outside Maryborough, Victoria, has been identified by Museums Victoria scientists and acquired for the State Collection. See it on display at Melbourne Museum next month, as part of the National Science Week Science on Show! event.

In May 2015, David Hole, a resident of Maryborough, Victoria, found the heavy and mysterious looking rock resting in yellow clay, around 2km out of Maryborough, while prospecting with a metal detector for gold. In 2018, still curious, Mr Hole brought this 38.5cm x 14.5cm x 14.5cm rock to Museums Victoria for identification.

Museums Victoria geologists Bill Birch and Dermot Henry suspected almost immediately that this was a meteorite. While suspected meteorites are often brought by the public to the museum, almost all of them are , in museum parlance, "meteor-wrongs". Following photography, moulding and weighing, analysis on a slice removed for research purposes confirmed that this humble-looking "rock" is an H5 ordinary chondrite meteorite. The term Chondrite means that this meteorite contains tiny crystallised droplets (chondrules), that formed by flash heating of the dust clouds of the early solar system. It was most likely formed in the asteroid belt between Mars and Jupiter.

Bill Birch, Museums Victoria Emeritus Curator in Geosciences, who lead-authored the scientific paper identifying and describing the Maryborough Meteorite (published today in the Proceedings of the Royal Society of Victoria) muses, "When you consider all the events this chunk of rock has experienced since its formation 4.6 billion years ago, it's really mind-boggling that we get the opportunity to hold it and study it today. How good is that?"

The last meteorite found in Victoria was discovered at Willow Grove, Gippsland, in 1995. It is an iron-nickel meteorite, and is named, as are all meteorites, for the location where it was discovered. The most recent Victorian meteorite to be formally described is Ballarat, which was found in the late 1860s, but not confirmed as a meteorite until 2002. It is regarded as a 'fossil' meteorite, because it was found in river gravels buried under basalt, where it had been carried after landing. That meteorite is currently on display in the Dynamic Earth exhibition at Melbourne Museum.

Dermot Henry, Head of Sciences at Museums Victoria, explains the incredible significance of meteorites for understanding our Solar System and the Universe, "Meteorites provide the cheapest form of space exploration. They transport us back in time, providing clues to the age, formation and chemistry of our Solar System (including the Earth).

He elaborates, "Some provide a glimpse at the deep interior of our planet. In some meteorites, there is 'stardust' even older than our Solar System, which shows us how stars form and evolve to create elements of the periodic table. Other rare meteorites contain organic molecules such as amino acids; the building blocks of life."

When this meteorite landed on earth is unclear. Carbon 14 testing suggests between 100 and 1000 years ago. While researchers cannot confirm an exact date of landing, multiple meteor sightings in the Maryborough district were reported in local news between 1889 and 1951. The Maryborough Meteorite may have hurtled through our atmosphere fairly recently.

The Maryborough Meteorite joins a collection of over 400 meteorite specimens, held by Museums Victoria. Museums Victoria holds some of the most famous and heavily-researched meteorites ever to be found and identified. This includes the Murchison Meteorite, which celebrates 50 years since it's discovery later this year.

The full description of the Maryborough Meteorite can be found in the current issue of Victorian Journal Proceedings of the Royal Society of Victoria, published today.

www.museumsvictoria.

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