91探花

Professor Paul Wiegert, Department of Physics and Astronomy, University of Western Ontario, will give a public presentation about meteorites on Friday, July 25, from 2 to 3:30 p.m. in the Duffy Science Centre, Room 204, at the 91探花.

During his talk, entitled Meteorites and The Danger from Impacts, Wiegert will discuss the properties of known meteorites, along with more exotic ones such as meteorites believed to have arrived from the moon and Mars. He will show some examples of meteorites and talk about the differences between them and ordinary rocks. He will also discuss the danger of the impact of a larger meteorite on Earth.

Meteorites are usually fragments of broken asteroids, and spend most of their life orbiting the sun in the same way as the planets, says Wiegert. If and when the path of a meteorite intersects with that of Earth, friction with the atmosphere produces a shooting star as the meteorite approaches Earth at speeds of up to 70 kilometres per second.

If the body of the meteorite does not burn up during its brief but fiery descent, it--or pieces of it--may reach the ground. Large meteorites may create a crater, but smaller ones may not cause much more than a small dent where they land.

Wiegert teaches astronomy and physics at the University of Western Ontario in London, Ontario. His research concentrates on the smallest bodies in the solar system, such as asteroids, comets, moons and meteors.

All are welcome to attend this free event.