A perfect trap for space rocks
The Nullarbor Plain is the world's largest single exposure of limestone bedrock, a vast, flat expanse of about 200,000 square kilometers. This former shallow seabed, formed from the skeletal remains of marine life during the Miocene epoch, creates ideal conditions for preserving extraterrestrial visitors. Its name derives from the Latin nullus arbor, meaning "no trees," which hints at its defining features: an arid climate and a lack of vegetation.
These characteristics make the Nullarbor a productive hunting ground for meteorites. The pale, uniform color of the limestone surface makes the dark, fusion-crusted space rocks stand out sharply. The extreme dryness, with annual rainfall as low as 150mm, slows the chemical weathering that would normally cause iron-rich meteorites to rust and disintegrate over time. The geologically stable surface, with minimal soil development, prevents meteorites from being buried. This exceptional preservation means that thousands of specimens have been found simply sitting on the surface, some with terrestrial ages of over 30,000 years.
A cosmic library on the limestone
Since the 1970s, scientific searches have recovered several thousand individual meteorites from the Nullarbor, making it one of the most productive collection areas on the planet, outside of Antarctica. The finds represent a record of the early solar system, providing samples of asteroids and other celestial bodies.
Among the most famous discoveries is the Mundrabilla iron meteorite. With a total known weight of over 22 tonnes, it is one of the largest meteorites ever found. The main mass, a colossal 12.4-tonne fragment, was found in 1966. Its composition is primarily an iron-nickel alloy, with silicate inclusions.
More recently, the strewnfield yielded the Bunburra Rockhole meteorite in 2007. This was the first meteorite to be recovered after its fall was tracked by the automated cameras of the Desert Fireball Network. This tracking allowed scientists to calculate its original orbit, tracing it back to the inner part of the main asteroid belt. Isotopic analysis of Bunburra Rockhole revealed it came from a previously unknown type of basaltic asteroid, one that was likely destroyed in a collision around 3.6 billion years ago.