Heat in MoscowJuly 29, 1916: A small fire ignites in the drought-stricken timber town of Matheson, Ontario. The next day, high winds drive the blaze through the town, killing at least 223.

July 29, 1957: The U.N. International Atomic Energy Agency (IAEA) is founded to inspect commercial nuclear facilities to confirm that they are not being used for military purposes.

July 29, 2010: A month-long heat wave that has sparked dozens of wildfires is capped off by an all-time record temperature in Moscow (at right). The 102 degrees F heat, combined with smog and smoke from the fires, causes dozens of deaths.

Photo: ZUMA Press

This feature is compiled by Peter Dykstra, an MNN contributor and publisher of Environmental Health News and The Daily Climate.