2017 North Korean nuclear test
| 2017 North Korean nuclear test | |
|---|---|
Graphic from the United States Geological Survey showing the location of seismic activity at the time of the test | |
| Information | |
| Country | North Korea |
| Test site | 41°20′35″N 129°02′10″E / 41.343°N 129.036°E Punggye-ri Nuclear Test Site, Kilju County |
| Period | 12:00, 3 September 2017 UTC+08:30 (03:30:01 UTC) |
| Number of tests | 1 |
| Max. yield | ~50–60 kilotons of TNT (210–250 TJ) based on Korea Meteorological Administration to ~160–400 kilotons of TNT (670–1,670 TJ) based on International Monitoring System seismic station data |
| Test chronology | |
North Korea conducted its sixth (and most recent to date) nuclear test on 3 September 2017, claiming it had tested a thermonuclear weapon (hydrogen bomb). While unconfirmed, analysts agree the test was likely of a thermonuclear or boosted fission weapon. The test took place at a high point of the 2017–2018 North Korea crisis.
The United States Geological Survey reported an earthquake of 6.3 magnitude not far from North Korea's Punggye-ri nuclear test site. South Korean authorities said the earthquake seemed to be artificial, consistent with an underground nuclear test. The USGS, as well as China Earthquake Networks Center, reported that the initial event was followed by a second, smaller, earthquake at the site, several minutes later, which was characterized as a collapse of the cavity formed by the initial detonation.
While early intelligence and academic reports suggested yields between 100 and 160 kilotons of TNT, later yield estimates were between 250 and 400 kilotons. Via the International Monitoring System, it was the first underground test where infrasound signatures were recorded transiting the thermosphere. North Korea had previously claimed it tested a hydrogen bomb in January 2016, but this was widely discounted by experts. Analysts were more favorable to a true thermonuclear weapon explanation for the 2017 test, while yield estimates reach the upper limits of the largest pure fission or largest boosted fission weapons ever tested.
The test was internationally condemned by countries throughout Asia, as well as the five permanent members of the United Nations Security Council. Japan and South Korea announced new missile defense measures, with South Korea seeking Terminal High Altitude Area Defense batteries from the United States. In November, the United States relisted North Korea as a State Sponsor of Terrorism.
In April 2018, North Korea announced a unilateral nuclear and intercontinental ballistic missile testing moratorium. From 2021 the country extensively tested cruise missiles and short-range ballistic missiles, and in 2023 resumed ICBM tests, while as of 2026 this remains the most recent confirmed nuclear test in the world.