The timing of it is one of the most fascinating things to me:
"At 1:23:04 a.m. the experiment began."
"With reactor output rapidly increasing, the operators pressed the AZ-5 ("Rapid Emergency Defense 5") button at 1:23:40"
"At 1:24, 20 seconds after the SCRAM was ordered, the first steam explosion took place"
"A second, more powerful explosion occurred about two or three seconds after the first:"
That's like one minute of elapsed time between them starting the experiment and having the biggest nuclear incident in history. Wow.