In 1957, during the Pascal-B nuclear test in Nevada as part of Operation Plumbbob, a 900 kg steel plate sealing a test shaft was violently ejected by the explosion. Based on a single image captured by an ultra-fast camera, scientists estimated the plate reached a speed of about 66 kilometers per second—nearly six times Earth's escape velocity. This speed would have allowed the object to break free from Earth's gravitational pull, raising speculation that it might have reached space before the Soviet satellite Sputnik in 1957. However, no physical evidence of the plate has ever been found. The Pascal-B test was designed to study how to contain nuclear explosions and their radioactive fallout underground. Engineers had dug a 150-meter-deep shaft, with a thick steel plate at the top intended to act as a massive stopper. The plate, about ten centimeters thick, was welded in place to withstand the immense pressure of the detonation. Physicist Robert Brownlee from the Los Alamos laboratory oversaw these containment efforts, working to predict how materials would behave under extreme conditions. Yet, no one anticipated how the plate would react to the explosion. On the day of the test, an ultra-fast camera captured the moment the steel plate was ejected. In a single frame, the plate was already seen leaving the shaft, seemingly torn away by an enormous force. The next instant, it vanished from view, leaving only a blurry image and a host of unanswered questions. Scientists used this image and the data from the explosion to calculate the plate's ejection speed, which was extraordinary and sparked urban legends about the first human-made object reaching space. Despite the calculated speed, the physical reality of Earth's atmosphere posed a significant challenge. At such extreme velocities, friction with the air would have generated immense heat, potentially vaporizing the plate before it could escape Earth's gravity. This is the most widely accepted explanation among experts, though no debris has ever been found to confirm it. The lack of a definitive answer has kept the story of the Pascal-B steel plate intriguing, as it remains an unresolved mystery. Some sources even claim the plate might be the fastest human-made object ever launched from Earth. Whether it vaporized in the atmosphere or somehow escaped into space, the story of the Pascal-B test continues to captivate both scientists and enthusiasts alike, highlighting the unpredictable nature of high-energy physics and the limits of our understanding.