Using GPS To Detect Secret Nuclear Tests

Harperdog writes "This article details how GPS can help detect secret nuclear tests, giving the US more reason to ratify the Comprehensive Test Ban Treaty. Here's a quote about the 2009 North Korea test: 'At the time, however, the May 25 bomb also sent a different signature, this one into the atmosphere. It did not release radioactive gas or dust, as would be the case for a bomb detonated on the Earth's surface. Rather, it released a shockwave — a bubble of disturbed air that spread out from the test site across the planet and high into the ionosphere. ... We quickly gathered data from 11 GPS receivers — six belonging to the South Korean GPS network and five belonging to the International GNSS Service and scattered around Eastern Asia. The data indicated a sudden spike in atmospheric electron density just after the underground test.'"

Comments

Total Electron Content

[dtmos]

This work actually measured Total Electron Content, not electron density (a related, but different, phenomenon).

Maps of vertical and slant atmospheric electron density over the U.S. are here.

US GPS satellites also have photodetectors

[daveschroeder]

The US GPS constellation (NAVSTAR) has photodetectors to detect the distinctive flash of an above-ground nuclear test, among other detectors.

Not useful for an underground test, but a little known function nonetheless.

Re:US GPS satellites also have photodetectors

[ColdWetDog]

I thought we could already detect underground tests with seismographs. That was how we identified the semi-successful .5 kT NK test, and identified a previous explosion in NK of similar magnitude as being non-nuclear in origin.

Yep, that's in TFA and in fact what they used to 'calibrate' this new system. However, having multiple methods of detecting something that people don't want to be detected is often useful.

Re:What does this have to do with the Test Ban Tre

[_0xd0ad]

When the Nuclear Test Ban Treaty was formalized in 1996, the United States was among nine nations that did not ratify it. In part, US officials objected that technologies of the time were not reliable enough to ensure accurate detection of secret nuclear tests.

Re:Overkill and/or reduncancy?

[Oxford_Comma_Lover]

So, you would propose watching for tweets about secret underground nuclear tests?

Better. I'd get government funding for it. =)

Re:What does this have to do with the Test Ban Tre

[Oxford_Comma_Lover]

> It has been U.S. policy from the beginning to maintain a nuclear stockpile that can function as a deterrent against the use of nuclear weapons by any and all others that have them.

To be fair, it was US policy at the beginning to build the bomb and win the second world war.

Any policies about stockpiles as a deterrent came later--I would guess the instant the Russians set off an A-bomb.

Re:GPS over Iran?

[Xaositecte]

You don't seem to understand exactly what happened in japan.

GPS sats already used to detect nuclear detonation

[Symnron]

GPS satellites contain a package called NDS or Nuclear detonation Detection System. They have since the very first launch of the very first satellite. I know this because I was in the USAF and worked the ground station for NDS starting with Block 1 GPS satellites when they were just early test platforms to prove the GPS technology. So, this is absolutely nothing new to me. Sincerely, Symnron Get Moose and Squirrel!