University of Alberta Space Physics

To the unaided eye, the night sky appears as a vast and empty void, while the daytime Sun has the appearance of a quiescent sphere of ambient light. The 150 million kilometers that separates Earth from the Sun is not in fact filled by empty space, but is instead populated by a high-speed "solar wind" consisting of solar protons, electrons and electromagnetic radiation. The interaction of the solar wind with planets that have an intrinsic magnetic field is extremely dynamic, involving large scale electric and magnetic field generation. In the case of planet Earth, the solar wind compresses the planets magnetic field on the dayside, whereas on the night-side it stretches it into an elongated magnetic cavity called the magnetosphere. The magnetosphere is very important in human terms as it acts as a partial shield against harmful effects of solar wind particles and radiation. Understanding the solar wind interaction with Earth is important for a variety of reasons, including how it affects climate and human evolution. It is also important in terms of how it affects technology, along with human activity in space and on the surface of the Earth.

Through advances in technology developed during the 20th century, scientists have discovered that Earth's upper atmosphere stretches thousands of miles into space. This invisible realm is filled with energy stored in charged particles, magnetic fields, and other rays invisible to our eyes. We actually live inside the atmosphere of the sun. The so-called "empty space" of our solar system contains in it the solar system equivalent of winds, clouds, storms, and hurricanes -- collectively, scientists refer to these as space weather. Just like weather on Earth, space weather can at times be very intense. Certain forms of space weather, such as coronal mass ejections on the sun, are extremely destructive to technological systems in space, as well as on the ground at both high and mid latitudes. 

Space Physics involves the study of charged particles and magnetic fields in the invisible realm above and beyond the atmospheres of planets. It includes the study of the Sun's corona, the ionosphere and magnetosphere of planets, the heliosphere, and the local interstellar medium. The ultimate challenge of space physics is to understand the physical concepts behind space weather and to someday be able to accurately predict it.

Ground-based observations of sun-spot cycles, cosmic rays, spectacular displays of the aurora borealis, and the pointing direction of comet tails, established the basic foundation for the development of the field of space physics. The development of plasma physics, and the launch of rockets and artificial satellites, opened the gateway to space plasma physics. It is now understood that solar activity and the sunspot cycle, control the flow of the solar wind, which in turn modulates cosmic ray intensities, as well as energizing the magnetospheres and ionospheres of planets. What we learn from studying our Sun and the environment of the heliosphere, can readily be applied to other stellar astrophysical objects and systems throughout the universe. Therefore, by studying space plasmas, we gain an understanding of the universe as a whole.

Present studies in space physics at the University of Alberta can be divided into the following topics:

- Global morphology of the polar ionosphere determined from optical and HF-radar observations

- The physics of magnetic storms and substorms

- The generation mechanisms for auroral arcs and associated nonlinear plasma instabilities

- Global simulations of Earth's magnetosphere and magnetospheres of other planets

- Relativistic particle energization and dynamics inside Earth's magnetosphere

- Remote monitoring of plasmaspheric dynamics

- Theoretical studies of nonlinear plasma instabilities associated with substorm dynamics

For more information on individual projects, please see the "People" pages in the "About Us" menu.