Manchester’s Antarctic meteorite hunters

A multi-disciplinary team from the University of Manchester is planning the UK’s first dedicated meteor hunting expedition to Antarctica for 2020. Antarctica is seen as the best place to hunt for meteors and has yielded tens of thousands of samples over the last 30 years.

Dr Geoffrey Evatt is leading the team and explained in a university press release why Antarctica is such an abundant source for meteorologists. Firstly, there is “a strong colour contrast between the icy surface and meteorites which are much darker” and secondly “there is a concentration of meteorites.”

The surface of the Earth is constantly being peppered with falling deposits and in Antarctica these deposits get trapped in the ice. As the glacial ice moves towards the oceans it sometimes comes up against mountain ranges which can force it to the surface, where it melts and leaves the meteors visible on the surface. This significantly narrows down the search area.

But the Manchester team is specifically searching for iron rich meteorites. The usual ratio of collected iron meteorites across the world is around 5.5 per cent but in Antarctica this falls to 0.5 per cent. The team has predicted that the missing meteorites are likely to be just below the surface.

Iron is a much better conductor of heat than rock so the team predicts that when meteorites with higher concentrations of iron approach the surface they transfer the sun’s rays to the ice below which melts and causes them to sink again.

The team will be using newly-developed advanced metal detectors during the 10-12 week expedition. They will be conducting a preliminary trial in 2018 on the Arctic island of Svalbard.

Dr Evatt said that although they won’t be looking for meteors, this would be an opportunity to test the equipment and “develop protocols for collecting samples” and also for “team bonding.” In 2019 they will go to Antarctica on a survey expedition to identify areas with visible meteorites with the aim of returning the following year to look below the surface at those sites.

They will be flying to very remote areas for the Antarctic expeditions where they will have to remain self-sufficient. During that time, they will face difficult conditions with incredibly high wind speeds of up to tens of metres per second. If the team is successful, Dr Evatt says that when they return home the real work can begin. Iron meteorites can tell us about the internal formation of planets and planetoids — smaller bodies of the Solar System which were largely destroyed through collisions — and thus about the origins of the Solar System.