[meteorite-list] Bucke Prize Adds to Astrnomer's Meteoric Rise (Peter Brown)

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Sat Mar 18 11:25:24 2006
Message-ID: <200603172136.k2HLaHl29813_at_zagami.jpl.nasa.gov>

http://communications.uwo.ca/western_news/story.html?listing_id=20887

Bucke Prize adds to astronomer's meteoric rise
By Mitchell Zimmer
Western News
The Univeristy of Western Ontario (Canada)
March 16, 2006

Sometimes the opportunities to learn about early solar system formation
drop from the sky. At least they do for 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.

Like a detective, Brown notes numerous factors as each body hits the
Earth -- the light 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, 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 on 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 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
as the bridge between the comet-and-meteorite debate. The best way to
corroborate this idea is to compare the meteor sample with comet
material gathered from the recently returned NASA Stardust mission.

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

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

The prize, recognizing superior research in the Faculty of Science, is
in memory of Florence Bucke (BA'26) who taught school in Fort Erie until
1971.

For more about the work of the Tagish Lake meteorite recovery team, check:

http://aquarid.physics.uwo.ca/~pbrown/tagish/photos.html
Received on Fri 17 Mar 2006 04:36:17 PM PST