Several observers noted a fireball event (a very bright meteor) in the skies of the region near dawn on Sunday, 06 May 2001. Reports have come from people at home or on the road at approximately 05:15 hours, local time, along a 300-kilometre axis north of Lake Ontario ( view sketch map). At least eight individuals or groups of people saw the remarkable sight, from the Port Perry area (two reports); Norwood; Thomasburg (south of Tweed); and four points in the greater Ottawa region, including two at Nepean and one at Meech Lake, in the Gatineau area of Quebec. One observer near Norwood reported delayed sound, audible inside his vehicle as he drove east along Highway 7.
The latest report to be received was from the area of McCraney Lake, in westernmost Algonquin park, northeast of Huntsville. The sum of observations can be interpreted in terms of a generally northward passage of the fireball, which in principle was visible over an area greater than 40,000 km2, roughly centred on Bancroft.
The American Meteor Society gathered reports from four witnesses across Massachusetts, New York and Pennsylvania. The fireball was said to be moving in a roughly northwest direction, to be white or bluish-white in colour, and to have a magnitude greater than -12 (extremely bright, more than the full moon). The A.M.S. attribute the fireball to the Eta Aquarid meteor shower, which reached its peak on May 5th and is associated with the famous comet Halley.
Most such events are explicable by the rapid passage of `cosmic debris' or the detritus of space vehicles re- entering Earth's atmosphere. On relatively rare occasions one or more fragments survive the rough passage and fall to Earth as meteorites. Residents of northern B.C. and the southwest Yukon were treated to a spectacular fireball on the morning of 18 January 2000. This event rained hundreds of small fragments onto the frozen surface of Tagish Lake. The total mass was reportedly about 12 kg. Another, on the evening of 14 June 1994, dropped some 25 kg of meteorites near the community of St-Robert, northeast of Montreal. Small meteorites falling in daylight may appear unheralded, except for the wind of their passage; such was the case of the small Kitchener meteorite, which fell next to a golfer on the sixth tee during a Sunday morning game on 12 July 1998.
People lucky enough to see a fireball often think that the event is close at hand, that it "fell over the next hill", whereas the falling body may have burnt up tens of km high in the sky, or landed 100 km away! However, typical calculations of the "pre-atmospheric mass" of meteorites reveals a fearsome attrition of the tumbling, violently buffeted and rapidly-heated visitors as they fall to Earth. It is hardly surprising that few bright meteor observations result in a fallen meteorite for the museum (note the distinction buried in this sentence)! In the case of the St-Robert fall, the 20-odd stones weighing 25 kg may be only 1-2 percent of the mass of the body in space, estimated to have been between 900 kg and 3 tonnes!
A group of Canadian astronomers and geologists concerned with meteors, meteorites and larger objects of the "Deep Impact" variety are known as MIAC , the Meteorites & Impacts Advisory Committee to the Canadian Space Agency. Scientists affiliated to MIAC would like to hear from anyone who witnessed the recent event. Anyone who saw it, and can provide details of the time, direction and appearance of the fireball, can contact MIAC via Prof. John Rucklidge at the University of Toronto (e-mail jcr@quartz.geology.utoronto.ca, telephone 416-978-2061) or leave a message locally at 705-653-5223.
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This is an expanded and updated version of the original press release, which appeared in the Community Press (Western Edition, p.12, 11 May 2001). I had inadvertently provided the wrong date (Monday 7th) but the hour and low population density of the region (Ottawa excepted) probably contributed to the modest number of known observers.