John Savard wrote:
The mushroom cloud occurred near their Daepodong missile base, and the
mushroom cloud was four miles in diameter (or more) and it occurred on
September 9th, the 56th anniversary of the founding of North Korea's
communist regime.

And they're saying they don't think it was an above-ground test of a
nuclear weapon?

Yes. We have numerous systems designed to test for such.
Including gamma radiation sensors (whence came the original
detection of cosmological gamma ray bursts), radionuclide
measuring systems (designed to monitor for the presence of
certain components of radioactive fallout in the atmosphere),
infrared sensors (for both missile launch and blast
detection), seismic sensors, and others. A below ground
carefully controlled low-yield test might, potentially,
evade these sensors if done right. An atmospheric test
would almost certainly not.


Well, I did hear it claimed that there was more energy in the fuel tanks
of a Saturn V rocket than in an atomic bomb. Perhaps North Korea's
attempt to put its first man into space failed?

Unlikely considering North Korea's capabilities, but not
completely out of the question.

For what it's worth, a Saturn V rocket contains much less
energy than a typical nuclear weapon, though it does
contain on the order of kilotons (TNT equiv.) of energy.
It does, after all, contain a few kilotons of high energy
chemical propellants. A Taep'o-dong 2, however, does not,
it contains merely tens of tonnes of propellant.