I believe the myth of the astronauts dying instantly. There is the possibility that sudden G shock may have caused them to black out, but that is just personal speculation, as I don't have the data regarding the speeds reached by the crew capsule after the initial explosion. The crew cabin can actually be seen in that famous video, shooting off away from much of the other debris, and it is still intact. Therefore, if the astronauts were not knocked unconscious, they likely were alive until slamming into the water at a fatal rate of speed. At those speeds, there is not much difference in hitting water or concrete, as the effects are the same.



I beg to differ regarding that cold did not cause the disaster. It was in fact because of the cold that this disaster happened, meaning that if it were warmer, this particular disaster would have been avoided. I am particularly well-versed and well-read in this aspect of the matter, and will attempt to explain my point. A company called Morton-Thiokol was tasked with the construction of the booster rockets used on the shuttle. To make a long story short, higher management were informed that there was a problem with the O-rings used to keep the propellent in its chamber. There are actually two O-rings, as one is a backup.



The company did nothing about the problem, and the night before the launch an effort was made by a group of engineers for the company to stop the launch the next day. MK had a conference call with NASA that night, and despite the warnings, NASA decided to go ahead with the launch. The problem is extremely easy to understand, now of course, being after the fact. But there were engineers who fully expected the launch to fail, because they knew it was too cold for the O-rings to perform correctly.



These particular rings were supposed to function by expanding when exposed to heat and pressure, effectively sealing the fuel tank by expanding snugly against and into the joints where they were positioned. However, since it was so cold, the O-rings became hard. Thus they were not pliable and would not expand nearly enough to close off the gaps in the fuel tank. In warmer weather this problem would not have been an issue at all. So both O-rings failed because of the cold, and despite whether there was an explosion or not, there was a huge leakage of fuel, and everything just went wrong from there.



Actually, on a previous shuttle mission, I believe an O-ring had failed as well. But luckily the backup O-ring remained intact. This was noted by the engineers at MK, but again, management I suppose wanted to keep the deadline that had been set, and didn't want to delay the launch again, for it had already been delayed on previous occasions, if I'm not mistaken.