Pieces of rock from space land on Earth every hour, says Professor Phil Bland of Curtin’s Department of Applied Geology, who has set up an ambitious project to match meteorites with their cosmic origins.
‘Shooting stars’ are not stars at all, explains Bland. They are meteors – streaks of light caused by small pieces of rock that burn up as they enter Earth’s atmosphere. Most are destroyed during their descent, but bigger rocks can make it to the ground.
“When one of these things lands on Earth, you’ve got a chunk of asteroid,” says Bland. “We’re amazingly lucky to get these samples, basically for free, from a whole bunch of different objects in the asteroid belt, even from Mars or the Moon.”
Bland and his team have set up a network of 32 cameras, 130 km apart, across much of remote Western Australia and South Australia, with the aim of triangulating meteorite trajectories as they approach Earth. From the photos, they can determine where in the Solar System the rock originated.
“It’s a lot trickier to work out where it will land on Earth,” says Bland. Factors like the size of the rock and whether or not it breaks up into fragments, as well as wind conditions, all affect where the pieces land. If it lands in the desert and the team gets to it quickly, it should be in pristine condition.
A sister project, Fireballs in the Sky, involves a smartphone app that the general public can use to record and report meteor tracks. If several people send in reports of the same meteor, Bland’s team can respond with details of its origin. “If you are out on a clear night, look up – I guarantee that in an hour you’ll see something amazing!” he says.
– Clare Pain