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The extravaganza was mounted barely six years after the Wright brothers took off at Kitty Hawk, N.C. in the first heavier-than-air manned flight.

Safety concerns increased in 2020 after a pipeline in Mississippi ruptured in a landslide, releasing a heavier-than-air plume of carbon dioxide that displaced oxygen near the ground.

Two brothers from Dayton, Ohio, conducted four machine-powered, heavier-than-air flights under human control on a single day in December.

The $2.1 billion rover will also come with the first helicopter, known as Ingenuity, that will let researchers understand the viability and potential of heavier-than-air vehicles on the Red Planet.

Like many scientifically minded people of that era, Christmas was infatuated with heavier-than-air flight.