Eastern Time, January 28, 1986. Under the strict selection and physical training of one out of ten thousand, the aircraft includes the historic first Asian-American (Onizuka Seiji) and the second African-American (Ronald McNair) aerospace expert, as well as the first civil aviation expert. Seven astronauts, including social science teacher Christa McAuliffe, are about to set off for outer space on NASA's "Space Shuttle Challenger", which has served less than 3 years. The 25th space shuttle flight expedition plan for the human spaceflight journey is also the 10th mission "STS-51L" since the space shuttle Challenger entered service. AP_421810736067 Photo Credit: AP / Dazhi Image Mr. McAuliffe In addition to the release of an artificial satellite to observe "Halley's Comet" (1P/Halley), and some basic scientific experiments (magnetism, etc.) field exercises, McAuliffe will also record two 15-minute lectures in the space shuttle. Instructional lessons are broadcast to millions of schoolchildren across the United States through closed-circuit video transmission. In fact, before departure,
the mission "STS-51L" was delayed for nearly 6 months due to system structural concerns and poor weather. In particular, the issue of the O-ring seal of the rocket thruster, which was originally related to the space shuttle flight and the safety of passengers, has been continuously raised by engineers for discussion: The O-ring must be perfectly sealed, and it must be 100% completely sealed to ensure that the high temperature and high pressure gas generated when the solid propellant is burned does not leak out, so that the solid propellant can also protect the requirements of manned missions . However, according to the previous return data feedback, wedding photo retouching services the elastic force of the rubber O-ring will decrease as the temperature drops, which will make the space shuttle unable to be squeezed to form a sealed state when it is launched, especially at 12 degrees Celsius. Rings create erosions of varying sizes…. At 9:30 a.m. on January 28, the temperature at the Kennedy Space Center in Florida was minus 3 degrees Celsius, yes, minus 3 degrees Celsius. At this time, the vice president of parts engineering and the vice president of the thruster project strongly suggested that the space shuttle should be postponed to launch, and then start the journey after the outdoor temperature rises,
there is no worry of insufficient O-ring sealing... However, after some private discussions and coordination, the senior officials of the space center believed that the scientific evidence related to the failure of the O-ring caused by low temperature was insufficient, and the error range of the so-called fault or erosion in the so-called report was not small, and decided to maintain the order launched that morning. At the same time, due to the low temperature last night (reported to be minus 13 degrees Celsius), the bottom of the fixed launch pad is now "frozen", and the icicles inside the launch pad are as long as 73 meters. Immediately afterwards, there were no other filing or shelving measures, and the space center chose to use a buffer of more than an hour, while waiting for the increase in sunlight to speed up the melting of ice, while letting government officials speak on the stage one by one. When the staff on the ground replied that the preparation procedures had been completed and confirmed that the icicles at the bottom of the launch pad had gradually melted away, in the auditorium next to the base, many relatives and friends of astronauts from all over the world also began to cheer and congratulate each other, wishing the space Shuttle can lift off on time after the end of the countdown program and fly to the vast expanse of space.