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Science

Andrew Yau probes the stormy Sun-Earth relationship

In March 1989, a giant solar storm sent clouds of charged particles, known as plasma, hurtling toward Earth from the Sun. The storm tripped a circuit in Quebec's power grid, causing a province-wide blackout.

"We can't see what's happening in space from Earth, yet we know that it affects us, sometimes critically," says Dr. Andrew Yau, Professor and Senior NSERC Industrial Research Chair in Experimental Space Science with the University of Calgary's Department of Physics and Astronomy.

The physics of plasma

Dr. Yau has spent much of his career probing the behaviour of plasma in outer space and he's leading the development of the Enhanced Polar Outflow Probe, ePOP. It will be launched on Canada's small, but powerful and versatile CASSIOPE satellite in 2008.

"Plasma makes up more than 99 percent of matter in the universe," explains Yau. "Solar storms and other space weather phenomena are caused by the physical processes of plasma. My goal is to understand these processes so we can predict their occurrence and reduce their effects."

ePOP will carry a suite of eight scientific instruments to collect data about the effects of solar storms on radio communications, satellite navigation and other space-based technologies.

A passion for reasoning and challenging conventional theory

Dr. Yau says he ended up in space research by accident. "In high school, I was motivated by a math teacher who instilled an appreciation of reasoning and logic rather than memorization of facts," says Yau.

A sounding rocket project called MARIE was, for Dr. Yau, a high point in his career. "The experiment I proposed was considered outrageous by some scientists. I was trying to disprove a long-held theory. Charged particles were thought to travel in one direction only, that is, from the upper part of the atmosphere, known as the magnetosphere up to 3000 km above the Earth, down toward the region called the ionosphere, some 300 km above the Earth. I was trying to prove that plasma travels in the other direction also, that is toward the upper reaches of the magnetosphere." 

Eventually, he was given the green light to test his theory and his experiment was a success. "The sounding rocket found that, indeed, many ions escape the ionosphere, " says Yau. Scientists now believe that better understanding of these processes in the upper atmosphere will dramatically improve our ability to forecast space weather. When a solar storm is forecast, preventative measures can be taken, so it won't have such adverse effects on communications satellites, navigation systems, and power systems.