A solar particle event affects computers at the Toronto Stock Exchange, forcing a halt to trading.

In solar physics, a solar particle event (SPE), also known as a solar energetic particle event or solar radiation storm, is a solar phenomenon which occurs when particles emitted by the Sun, mostly protons, become accelerated either in the Sun's atmosphere during a solar flare or in interplanetary space by a coronal mass ejection shock. Other nuclei such as helium and HZE ions may also be accelerated during the event. These particles can penetrate the Earth's magnetic field and cause partial ionization of the ionosphere. Energetic protons are a significant radiation hazard to spacecraft and astronauts.

The Toronto Stock Exchange is a stock exchange located in Toronto, Ontario, Canada. It is the 10th largest exchange in the world and the third largest in North America based on market capitalization. Based in the EY Tower in Toronto's Financial District, the TSX is a wholly owned subsidiary of the TMX Group for the trading of senior equities.

August 16 is the 228th day of the year in the Gregorian calendar; 137 days remain until the end of the year.