To determine the cause of such a fire, investigators rely on a number of observations and techniques, from telltale signs of flames to satellite imagery and chemical tests.

To better understand the science, National Geographic spoke with Richard Meier, a fire investigator in Sarasota, Florida, with John A. Kennedy and Associates, which analyzes fires and explosions for insurance companies and trials. Meier is also a staff member at the National Association of Fire Investigators, and the organization's treasurer.

There's a lot of different ways. In my case I spent about 23 years in engineering, in the manufacturing industry, which is a good thing: I used to make things, so I know how they work. A lot of people start off