The first-ever cell phone call was made in 1973 by Martin Cooper, a researcher, and executive at Motorola
The person he called was his main rival Joel Engel, an engineer at Bell Labs, who was also working on the world's 'first' cellphone
Mark Twain was born on the day when Halley's Comet flew past Earth. He once said, "I came in with Halley's Comet in 1835. It is coming again next year, and I expect to go out with it"
Mark Twain died on April 21, 1910—the day after Halley's comet returned