nuclear question, page 1

Originally posted by Fiorina 161
thought i still think that the lines are made by the emp pules that come with an above ground det.

Originally posted by SilentFrog

Originally posted by Fiorina 161
dose anyone know if you get an emp if the det
is under ground?

Well, EMP happens when the energy release of a nuke (which is 90% photons immideatley after the explosion) doesn't get converted to heat. This can only really happen in the upper atmosphere, where there isnt much to absorb and remit the EM rad, which is why the US and USSR had nukes wired to go off there. You'll still get major EM radiation when a nuke goes off, but the vast majority will be in the IR, ie heat range.

And range of EMP pulse is huge compared to other effects.

The Thor missile carried the test instrumentation and the W-49 warhead/Mk-4 RV payload to 248 miles. The test appeared quite spectacular from Hawaii (800 miles away) and at Kwajalein (1600 miles away), with impressive light displays from an artifical aurora lasting up to seven minutes. The electromagnetic pulse (EMP) from this test sent power line surges throughout Oahu, knocking out street lighting, blowing fuzes and circuit breakers, and triggering burglar alarms.
Starfish Prime:
nuclearweaponarchive.org...

EMP is formed in high altitude explosions when the downwardly directed gamma rays encounter denser layers of air below. A pancake shaped ionization region is formed below the bomb. The zone can extend all the way to the horizon, to 2500 km for an explosion at an altitude of 500 km. The ionization zone is up to 80 km thick at the center. The Earth's magnetic field causes the electrons in this layer to spiral as they travel, creating a powerful downward directed electromagnetic pulse lasting a few microseconds. A strong vertical electrical field (20-50 KV/m) is also generated between the Earth's surface and the ionized layer, this field lasts for several minutes until the electrons are recaptured by the air. Although the peak EMP field strengths from high altitude bursts are only 1-10% as intense as the peak ground burst fields, they are nearly constant over the entire Earth's surface under the ionized region.nuclearweaponarchive.org...

Fo ground/low atmosphere detonations EMP is negligible/it's radius is so small that shockwave crushes/fireball's radiation burns everything inside it in every case.

EMP is also totally invisible to eye... except for "frying" of electronics caused by it.