For many wannabe astronauts, the idea of venturing into the great unknown would be a dream come true. But over the past 50 years, there’s been a slew of spaceflight-related tragedies that are more akin to an astronaut’s worst nightmare.
In the last half-century, about 30 astronauts and cosmonauts have died while training for or attempting dangerous space missions. But the vast majority of these deaths occurred either on the ground or in Earth’s atmosphere — below the accepted boundary of space called the Kármán line, which begins at an altitude of about 62 miles (100 kilometers).