You could drive to outer space in just one hour if your car could travel straight up at highway speeds.

The internationally recognized boundary of space is called the Kármán line, named after Hungarian-American physicist Theodore von Kármán. In the 1950s, Kármán calculated that at an altitude of approximately 100 kilometers (62 miles), the atmosphere becomes so thin that an aircraft would have to fly faster than orbital velocity to derive enough aerodynamic lift to support itself. This specific height was later adopted by the Fédération Aéronautique Internationale (FAI) as the official beginning of space.While reaching this altitude only requires traveling 62 miles, staying there is a much greater challenge. To achieve a stable low Earth orbit, a spacecraft must reach a horizontal velocity of roughly 17,500 mph (28,000 km/h). This speed allows the craft to constantly 'fall' around the curve of the Earth rather than falling back to the surface due to gravity. This distinction explains why suborbital flights, like those by Blue Origin, require much less energy than orbital missions like those performed by SpaceX.The proximity of space highlights the fragility of our atmosphere. For perspective, the distance to the Kármán line is less than the length of the state of Rhode Island or the distance between London and Brighton. Most of Earth's atmospheric mass is actually concentrated within the first 10 miles (16 kilometers) of the surface. This means that the life-sustaining air we breathe is a remarkably thin layer compared to the overall size of the planet.