Evrim Yazgin
Cosmos science journalist
Antarctica’s inhospitable, wind-swept ice desert has produced five new meteorite finds – including a mammoth weighing in at 7.6 kilograms.
In science, size isn’t all that matters. But we still love a thing that’s bigger than other things of the same type.
Finding a space rock of this size is a very rare find, but not unheard-of.
While undoubtedly large, it is a minnow compared to other finds.
The largest meteorite ever found in Australia is the Mundrabilla meteorite discovered in 1966 on the Nullarbor. The 12-tonne rock is now at the Western Australian Museum. But the largest in the world is the Hoba meteorite discovered in Namibia, weighing around 54 tonnes. Discovered in 1920, the meteorite is so big, it has never been moved.
The researchers who discovered the new haul of meteorites estimate that, of the roughly 45,000 meteorites detected in Antarctica, only around 100 are of similar or greater size.
“Size doesn’t necessarily matter when it comes to meteorites, and even tiny micrometeorites can be incredibly scientifically valuable,” says Maria Valdes, a research scientist at the Field Museum and the University of Chicago, “but of course, finding a big meteorite like this one is rare, and really exciting.”
Read more: 2022 – a rock-solid year for geology
Valdes was one of four scientists on an international team led by Vinciane Debaille of the Université Libre de Bruxelles.
The team’s mission was to explore, for the first time, potential new meteorite sites found using satellite imagery.
“Going on an adventure exploring unknown areas is exciting,” says Debaille, “but we also had to deal with the fact that the reality on the ground is much more difficult than the beauty of satellite images.”
Although their trip occurred in the Antarctic summertime, temperatures during the expedition were around -10° C. But the mission proved worth it.
Antarctica is a hotspot for meteorite discoveries. This is because the cold, dry ice desert continent reduces weathering experienced by the space rocks. Also, the white snowy and icy landscape makes spotting the black meteorites much easier than in other parts of the world.
Even when meteorites have sunk below the ice and snow, the churning motion of Antarctica’s glaciers often re-exposes the space rocks near the surface where their hue contrasts, making them stand out.
Read more: Earth’s core may have paused and might even be reversing, says new study
The five meteorites in the latest bunch will be analysed at the Royal Belgian Institute of Natural Sciences. In the meantime, sediment which may contain tiny “micrometeorites” will be studied by the researchers on the team at their respective institutions.
Valdes says “studying meteorites helps us better understand our place in the universe. The bigger a sample size we have of meteorites, the better we can understand our Solar System, and the better we can understand ourselves.”