Percy Spencer was naturally inquisitive. In 1910, he was just a teenager when electricity came to his community in rural Maine; he quickly figured out how it worked and installed it in a local factory.

When he grew up, Spencer worked to pump out radar equipment for Raytheon during World War II. He worked seven days a week as he kept trying to make improvements to the systems.
 
One day, as Spencer worked with a part of a radar called the magnetron, he noticed the candy bar in his pocket getting hot. This tiny detail led him to ask the fateful question: Would this happen to other foods?
 
He began experimenting with popcorn kernels, which started popping all over the room. Then he moved on to an egg. Inevitably, it exploded on a co-worker’s face.
 
Early microwave ovens – like other early technology – were not exactly consumer-friendly. They weighed 750 pounds, clocked in at six feet tall, and cost thousands of dollars.
 
Although microwaves were presented as a futuristic convenience in the late 1960s, they didn’t become household fixtures until the 1980s, after Spencer had passed away.

Without Spencer’s work on radar: no Hot Pockets, no nuking the leftovers, no neon-colored popcorn. It’s an America we’d hardly recognize.

This segment originally aired on January 29, 2015. It was rebroadcast and updated on September 16, 2017.