Catalogue of Canadian meteorites

By: Graham C. Wilson, University of Toronto

The Canadian meteorite recovery rate is modest. Only a dozen have been recovered in the province of Ontario, which is five times as big as the state of Kansas where over 110 known meteorites have been collected. Low population density and inclement weather may conspire with terrain and land-use factors to hinder recovery of falls and finds alike.

Discredited specimens

Physical specimens have been documented for Akpohon and Leeds. Takysie Lake and Otasawian. No material was recovered in the case of the Eastman and Prince George, which were included here only for consistency with earlier meteorite catalogues. In addition, dozens and probably hundreds of 'meteorwrongs' have been diagnosed over the years by Canadian museum and university staff. All kinds of slag and metallurgical products, mafic-ultramafic rocks, hematite nodules, pyrite spheroids, geodes and other natural terrestrial rocks are considered remarkable by their finders, for reasons of circumstance, density, texture, shape and other features. The finders should not be discouraged; in every few dozen meteorwrongs there is often a meteorite. The latter are sometimes part of an abundant shower or major find, and sometimes a true unknown, new to science.

Water-bearing meteorite

A white and glowing 1kg meteorite that was discovered by a group of boys playing basketball in a driveway in a small town in West Texas contains the first extraterrestrial water ever captured on Earth. Dr. Michael Zolensky, a mineralogist with NASA's Johnson Space Centre in Houston was part of a team that found purple halite crystals, complete with fluid inclusions in the 4.5 Ga chondrite meteor. The inclusions contain primordial water that may have existed in interstellar space before the sun and planets were born. The amount of chlorine in rocks, especially meteorites, is pretty low so there was either a huge quantity of water associated with the rock, or there is some unknown other mechanism for making sodium chloride. Two possible origins for the brines are indigenous fluids flowing within the asteroid and exogenous fluids delivered into the asteroid surface from a salt-containing icy object.