UPDATE 2/9/2023: The balloon had equipment that was "clearly for intelligence surveillance," including "multiple antennas" that were "likely capable of collecting and geo-locating communications," according to a statement by a senior State Department official. The official said the balloon is likely part of a huge aerial spy program operated by the Chinese military that has targeted more than 40 countries on five continents with high-altitude surveillance balloons similar to one the U.S. sh
Research Overview
Background: The detonation of a nuclear weapon at high altitude or in space (~30 km or more above the earth’s surface) can generate an intense electromagnetic pulse (EMP) referred to as a high-altitude EMP or HEMP. HEMP can propagate to the earth and impact various ground-based technological systems such as the electric power grid. Depending on the height of the explosion above the earth’s surface and the yield of the weapon, the resulting HEMP can be characterized by three haz
