Some of those Thiokol engineers expected o-ring failures at liftoff.

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In the case of the Challenger, the culprit was a simple O-ring that had become too brittle to do its job after a freezing night waiting on the launch pad.

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Way back in November of 1985, on just its second mission, Atlantis experienced a blow-back of hot gases past the primary O-rings in one of its solid rocket boosters, resulting in serious erosion of said O-ring.

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Differentiating an O-ring is no easy task.

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Fossil also offered a slick LCD watch with its Philippe Starck O-Ring Digi Watch for Fossil, which provides a clear visual reminder of when its time to get your wrist hair waxed, but the hipsters at Tokyo Flash have struck out with the JLr7. a timepiece that brings incredible complexity to what should be a simple act of telling time.

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