ONTARIO—A bright flash of light. A streak across the sky. One object fragments into four bright stars, shimmering momentarily before fading into the inky black night surrounding them.
That’s what lucky spectators saw the evening of November 28 around 9:15 pm when a meteor entered the atmosphere somewhere close to Toronto, creating a dazzling show for viewers from New York State to Northern Ontario, possibly as far as eastern Massachusetts.
“It was certainly a lot bigger than usual, and especially in Toronto, to see something like that, it would have had to have been pretty large to get through the light pollution,” says Emily Deibert, a PhD student in astronomy and astrophysics at the University of Toronto (UofT).
“I didn’t see it myself, but I happened to be on Twitter, so I saw a lot of people live-tweeting the sighting,” she says.
In addition to the many reported civilian sightings through the American Meteor Society (AMS), UofT’s Scarborough campus observatory has a webcam that picked up the fireball through an automatic detection program that tweets video footage of possible incidences. Five users have uploaded dash cam footage onto the AMS sighting website and the CN Tower captured it on its Edgewalk webcam.
This meteor is considered to be a fireball, a term that describes meteors that are quite bright, brighter than the planet Venus.
“This meteor was relatively bright, but not extremely bright,” says Hanno Rein, associate professor of UofT’s Department for Physical and Environmental Sciences and the director of the Centre for Planetary Sciences. The UofT observatory camera is part of Western University’s camera network but was the only camera in the system to detect the meteor. As such, the organization has been unable to triangulate a ground track of the meteor.
Ms. Deibert says that although meteors are fairly common, many fall in uninhabited areas where they will never be seen by a human eye. Others are so small that they do not cause much more than a brief, faint streak of light.
“There are a lot of small rocks or objects in space and millions of these collide with the Earth every night,” she says. “In a location with a dark enough sky, for example, Northern Ontario, you could probably expect to see a handful of these ‘shooting stars’ each night.”
As for terminology on earth, meteors are the pieces of rock or metal that burn up in the atmosphere, while meteorites are chunks that survive to land on Earth’s surface. Ms. Deibert says about 90 percent of meteors burn up in the atmosphere.
Meteors, even impressive fireballs like the one that occurred last week, are difficult to predict as one-off occurrences. Meteor showers, however, occur when large, known asteroids pass by Earth and small pieces fall off and enter the atmosphere. These are so large that their orbit can be tracked and forecasted, allowing for rough predictions as to when they will occur.
Next week, the Geminids meteor shower arrives to Earth with a peak around December 13 and 14. Ms. Deibert says this meteor is too early to be associated with the shower, but that more fireball sightings could be possible during the main event.
Having millions of objects collide with earth every night could point to a disastrous outcome, but given the nature of these small interstellar visitors, Ms. Deibert says the majority are unnoticeable. In extraordinary cases, even a small object that survives its fall through the atmosphere could do considerable damage because of its high velocity. A major meteor could even cause a pressure shockwave through the air that would be similar to an explosion. However, these incidents are exceedingly rare.
Instead, meteors are perhaps another way the universe offers both information and entertainment to us mere mortals on the ground.
“It’s nature’s way of putting on a fireworks show for us,” says Ms. Deibert, explaining that different elements give off different colours of glow when heated, much in the same way that manufactured fireworks use different materials to create a particular colour pattern.
“A green colour in the meteor’s tail, like many people reported, probably means that there is nickel present in the meteor. This can tell us about where the meteor might have originated. We can also study the materials that make up meteorites to learn more about what the Solar System was like when it was young, because a lot of meteorites haven’t changed much since they originally formed. Studying them helps us piece together an origin story of the Solar System,” says Ms. Deibert.
It seems only fitting that this nickel-containing meteor has been spotted in Northern Ontario’s Nickel Belt, a landform that had been formed by a meteor’s impact nearly two billion years ago. This streak in the sky might just have been a small piece of Sudbury returning home to its place in the Nickel City.