Building a Magnetosphere - One Particle at a Time

Dr. Eric Donovan

The Sun's atmosphere, the corona, is hot enough that its particles have escape velocity, and expand upwards and outwards through interplanetary space as what we call the solar wind. This electrically active plasma interacts with the magnetic fields it encounters, including that of the Earth, creating planetary environments called magnetosphere's. Earth's magnetosphere is the outermost part or our environment, and hosts a rich mixture of physical processes that create the radiation belts (discovered by the University of Iowa), and power the aurora. The magnetosphere is interesting as an example of a cosmic environment, and as something that matters for our economy. For my own research, I create observations of the aurora, which we use to remote sense this otherwise invisible domain.

With this talk, I follow the trajectories of individual charged particles through this system, and build up a picture of how protons and electrons of solar and terrestrial origin populate this rich environment. Using empirical knowledge of the solar wind and Earth's magnetic field, and techniques and methods from second and third year classical mechanics and E&M, I build up, particle by particle, a global system. The result is an incomplete picture, but one from which we can infer what some key properties of what the magnetosphere, and the aurora must be. My objective is to connect basic physics at the undergraduate level to front-line space physics, at the cutting edge of research in our field.

To participate in this event virtually via Zoom, go to https://uiowa.zoom.us/j/94219370434.