Comments by "MRA" (@yassassin6425) on "Challenger Explosion, Live Audience Reaction, 25th Anniversary" video.

@Complicate2k Both incorrect. An O-ring, a circular gasket that sealed the right solid rocket booster breached. The O-Rings were never tested in freezing temperatures and during the morning of the launch, the cold rubber became stiff failing to fully seal the joint. During the ascent, this allowed a plume of superheated exhaust gases to bath the hull of the external fuel tank (containing LOX and LH2) to rupture. As the launch vehicle disintegrated, the orbiter was turned broadside on into the M.2 airstream at 46,000ft and was torn apart by aerodynamic forces.
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