- June 12, 2019 - Planétarium : Astronomical News
June 14, 1994, is a memorable date in Québec history. That evening at 8:02 a fireball crossed the sky of southern Québec. A few moments later, meteorite fragments pelted the little village of Saint-Robert, about 60 kilometers northeast of Montréal.
The fireball was spotted over a radius of 500 kilometers reaching from southern Québec to Ontario by way of New York State, Vermont, and even New Hampshire.
An immense racket
The Sun had yet to set at the moment of the fall, which explains why a number of people failed to see the bolide go by, although they heard it. And what a din that must have been! A powerful, distinct boom, like a huge thunderclap or an airplane breaking the sound barrier. Residents less than 30 kilometers from the point where the fragments fell heard three to four blasts, followed by a thumping sound corresponding to the impact of the meteorite fragments on the ground.
At the point where it entered the atmosphere, the meteorite was moving at a speed of over 45,000 km/h. As it passed over Michaudville, the shockwave created by the meteorite produced the principal boom. After that, the meteorite broke up into several pieces, the biggest of them making their own, less intense, detonation.
A fragment found courtesy of cows
The first fragment was found just a few minutes after its fall. A young man, Stéphane Forcier, was intrigued by the behavior of certain cows on the family farm. When he went to check on what had captured the heifers’ attention, he discovered a stone weighing 2.2 kilograms.
In all, 20 fragments were found, representing a combined mass of 25 kilograms, first prize going to Pierre Sasseville, who found seven of them after creating a homemade detector with a modified ski pole.
A 4.5-billion-year-old stone
The study of the meteorite fragments allowed astronomers to re-create the history of this celestial stone. The mother asteroid of the Saint-Robert meteorite was formed 4.565 billion years ago. Then, two million years ago, a piece 65 centimeters long and weighing more than 1,500 kilograms was ejected from the asteroid. Thus began a long journey through space, which came to an end on June 14, 1994. That evening the stone fragment encountered the Earth, consuming itself almost completely in a celestial fireworks display that lit up the Québec sky.
The Saint-Robert meteorite is the only fall of meteorites ever observed in Québec, making the event truly one-of-a-kind. Let’s just hope we don’t have to wait another 25 years to observe another one.
