2006 Awards for Excellence in Research:
Dr. Peter Brown wins Bucke Prize

Dr. Peter Brown in his laboratory

Bucke Prize Adds to Astronomer’s Meteoric Rise

Sometimes the opportunities to learn about early solar system formation drop from the sky. At least they do for Dr. Peter Brown in the Department of Physics & Astronomy who is this year’s recipient of the Florence Bucke Prize.

The possible hazards of comets and meteors falling to Earth have been a source of fear throughout history, even today the subject of plummeting asteroids takes up substantial space in news headlines and movie screens. Brown agrees that such collisions are on people’s minds and observing asteroids with the Elginfield Telescope is one small facet of his research. However, his main interest focuses on the total influx of the fallen material. By understanding the origin and evolution of this material he is able to infer the composition of sectors of the solar system.

Much like a detective, Brown notes the numerous factors as each body hits the Earth, the light that it produces, the heat, even the sound helps him to understand things about it. Further field work involves collecting fragments and then reconstructing its mass, its physical properties and most importantly its orbit prior to hitting the earth, “that tells you something about its origin,” says Brown. “Does it come from the asteroid belt or does or come from a comet? What are all the different pathways that material makes its way to Earth? Those are the things we’re interested in.”

One of the more prominent debates in the field hinges on a growing belief that there is an artificial distinction between asteroids as rocky bodies and comets made mostly of water ice. The recovery and study of the Tagish Lake meteorite from the Yukon has provided some startling information for this debate. The fragments have “proven to be completely novel in the sense that it’s a new class of meteorites,” says Brown. In fact, he says that when the orbital, physical and chemical analyses are all considered, the evidence “all point to this being the first material from the outer solar system, the very farthest part of the asteroid belt, that we’ve actually seen here on the Earth. Of course, that’s of enormous interest in that we previously haven’t been able to sample that part of the solar system.” Even though the meteorite is from the outer asteroid belt, its physical properties are much closer to comets. Brown views the Tagish Lake sample to be the bridge between the comet and meteorite debate. The best way to corroborate this idea is to compare the meteor sample with the cometary material gathered from the recently returned NASA Stardust mission.

Brown will present a public formal lecture based on his work entitled "Comet and Asteroid Impacts: Hazards and Opportunities" on Thursday March 30 at 7:30 p.m. in Somerville House Room 3345 where he will be given the prize.

The Bucke Prize is part of the ever growing list of accolades for Brown, he currently holds the position of Canada Research Chair in Meteor Studies.

The prize, intended to recognize some of the best research in the Faculty of Science, is in memory of Florence Bucke (BA'26) who taught school in Fort Erie until 1971.