04-18-2018 10:16:00 AM -0700
04-16-2018 01:32:51 PM -0700
04-16-2018 09:59:36 AM -0700
04-12-2018 09:53:41 AM -0700
04-10-2018 11:19:03 AM -0700
It looks like you've previously blocked notifications. If you'd like to receive them, please update your browser permissions.
Desktop Notifications are  | 
Get instant alerts on your desktop.
Turn on desktop notifications?
Remind me later.

Can We Actually Even Tell if Humans Are Affecting the Climate?

From films and debris, it appeared that the solid rocket motors had failed first, sending a blowtorch of hot gas into the external tank, which then exploded. The solid rocket motors were built of a stack of components containing the solid fuel, which were then joined to make the whole rocket motor; it appeared, in fact, that one of the joints had failed.

One proposed explanation was that the cold has made the O-ring seals at the joints stiff. During a public, televised hearing, management people from the solid rocket manufacturers discounted this idea. Feynmann, who was one of the members of the all-star panel doing the investigation, quietly got a salt shaker and a glass of ice. They had a sample of the O-ring material that had been provided as a prop for the hearing. Feynmann put the salt into the ice, making a concentrated salt solution with a temperature much lower than the normal freezing point of water. Feynmann, without making a fuss about it, dropped his sample of O-ring in the water and let it chill.

Here's the strong-inference part of this. The Thiokol managers' hypothesis was that the O-ring material remained "sufficiently" flexible at the temperature it would have reached on that unusually cold Florida morning. Feynmann's experiment simply said "okay, so let's get a piece of this stuff cold and see what happens."

The answer, which Feynmann proceeded to demonstrate in a nationally televised hearing, was that the stuff got to be very brittle. Feynmann took what had been a soft, rubbery material at room temperature, and it broke like glass.

So much for the managers' hypothesis.