LONDON, Ont. — A small, angular rock that one Canadian physicist says looks like a chunk of black cheese has the potential to help scientists understand how the early solar system formed.
Peter G. Brown, a professor of physics and astronomy at the University of Western Ontario, says the meteorite made its fiery way to Earth on Oct. 3, after spinning out of its orbit in the asteroid belt between Mars and Jupiter, nearly 180 million kilometres away.
It tore through the roof of a home in Golden, B.C., narrowly missing the head a sleeping woman.
Brown says the woman has loaned the rock to the university and, for the next month or so, it will become "a small piece of a larger puzzle" as scientists "disentangle how the early solar system formed."
He says the 4.5 billion-year-old meteorite is older than anything on Earth but is formed of minerals found here, like iron and nickel, although in much larger proportions, giving it unusual weight for a rock its size.
The exact chemistry is still being studied, but Brown says the findings will link the rock to specific asteroids spinning beyond Mars, while his goal is to use photos of the Oct. 3 fireball to compute the meteorite's orbit, then merge the chemical and physical data to track the rock's origin.
It will eventually be returned to the woman whose roof it punctured, but Brown says it will first have given scientists a peek at how the asteroid belt formed, how asteroids evolved and how all that played a role in the formation of the planets.
"This piece is sort of a primitive piece of the original material that formed in the early solar system," Brown says in an interview from his office in London, Ont.
"The sheer quantity of information that's hidden in the rock that we can tease out, in a lot of ways it's like a really, really dense messenger of information about the early solar system."
The recovery of this meteorite and the associated photos of its fireball over southwestern Canada are fairly rare, Brown says.
It happens only once every five or ten years, but he says the data produced will be combined with similar events elsewhere in the world.
"We are building up a bigger statistical collection of these sorts of samples with spatial context but each one is unique, and it certainly makes the meteorite science a lot more valuable to know what the original orbit was of the object."
"We learn a lot of new things about the solar system each time we do this," Brown says.
Initial analysis of the meteorite could take a few weeks to a month, but more detailed examination "could go on for years," he says.
This report by The Canadian Press was first published Oct. 15, 2021.
The Canadian Press