What Happens if a Nuke Goes Off in Space?

Russia may be planning to put a nuclear weapon in orbit. We have known since the 1960s why that is a bad idea

By Allison Parshall, June 13, 2024

"The auroras over Hawaii on the night of July 8, 1962, were unlike any that humans had ever witnessed. 'N-Blast Tonight May Be Dazzling; Good View Likely,' read a headline in the Honolulu Advertiser beforehand. Nine seconds after 11 P.M., a startling flash set the sky aglow like eerie daylight, slowly fading from green to yellow to orange before settling on a vivid, unsettling red.

"The U.S. had just detonated a thermonuclear bomb 100 times more powerful than the one dropped on Hiroshima. Launched on a missile from Johnston Atoll, a U.S. unincorporated territory between the Marshall Islands and Hawaii, the bomb exploded at 250 miles above Earth’s surface—around the altitude in #LowEarthOrbit of most modern-day satellites. This event, called #StarfishPrime, wasn’t the first or last time that the U.S. or Soviet Union tested nuclear weapons in space (there were more than a dozen tests between 1958 and 1962), but it was the most impactful. The blast generated a power surge over the Pacific Ocean that knocked out about 300 streetlights on the island of Oahu—and destroyed or damaged about a third of the roughly two dozen satellites then in orbit.

" 'The Starfish Prime shot is sort of the poster child for why we don’t like nukes blowing up in space,' says Jonathan McDowell, an astrophysicist at the Center for Astrophysics | Harvard & Smithsonian. Indeed, only a few years later, in 1967, both the U.S. and the Soviet Union signed on to the Outer Space Treaty, which forbade putting weapons of mass destruction in orbit.

"Now, some six decades after the last nuclear detonation in Earth orbit, the threat of another has emerged with the Department of Defense warning about a potential Russian program to place a nuke in space. When the United Nations Security Council recently put forward a resolution to reaffirm the ban on such weapons, Russia vetoed the measure. U.S. officials have said there is no 'imminent threat' because no warheads are known to be in space.* But they have deemed the prospect 'deeply troubling' because a nuclear detonation there today would be far more destructive than even Starfish Prime."

Read more:
https://www.scientificamerican.com/article/what-happens-if-a-nuclear-weapon-goes-off-in-space/

#NukesInSpace #NoNukesInSpace #LEO #KesslerEffect #KesslerSyndrome #NoNukes #NoWar #NuclearWeapons #Satellites

Orbiting Armageddon: Russia’s #EMP Threat from Space and Transatlantic Responses

Apr 17, 2025

Excerpt: "If a #NuclearBomb were detonated in orbit, the physical effects would be unlike a typical terrestrial nuclear blast. There would be no mushroom cloud or shock wave in the vacuum of space. Instead, the weapon’s energy would be released as intense radiation and electromagnetic pulses (Scientific American).

"#Satellites within line of sight of the explosion would be instantly subjected to a blinding flash of gamma rays and X-rays, likely frying their electronics on contact (Scientific American). Moments after, a powerful #EMP would form as the bomb’s gamma radiation ionizes the upper atmosphere. This process, known as the #ComptonEffect, releases billions of high-energy electrons that race along Earth’s magnetic field lines (Scientific American). The result is an expanding wave of electromagnetic energy.

"U.S. defense officials have described this kind of space-triggered EMP as a 'massive energy wave' that could 'destroy satellites' and disrupt a vast swath of the satellites that the world depends on for communication and commerce (Carnegie). In essence, one orbital blast could simultaneously knock out numerous satellites – military and civilian – that are crucial to GPS navigation, telephone and internet links, financial transactions, weather forecasting, and more.

"An EMP from space could also induce chaos on the ground. The pulse would interact with Earth’s atmosphere and magnetic field to send geomagnetically induced currents surging through power lines and electronic networks (Aerospace America). In 1962, the U.S. #StarfishPrime test proved this danger: although detonated 400 kilometers above the Pacific, its EMP caused voltage spikes that blew out 300 streetlights and knocked out telephone lines in Hawaii, nearly 1,500 kilometers away (Scientific American , Aerospace America).

"An orbital detonation today, especially if positioned over populated regions, could overload electrical grids across vast areas. Transformers and grid infrastructure could be destroyed by the sudden, uncontrolled currents (Aerospace America). The scale of blackout could range over one or several countries, depending on the weapon’s altitude and yield. Experts warn that such a scenario would be devastating.

"A U.S. Congressional commission on EMP found that a nationwide power outage caused by a high-altitude nuclear blast could collapse critical infrastructure – an outcome it described as a potential
'civilization killer' if power and services were not restored quickly (Carnegie). In addition to massive economic damage, the disruption of communication and radar networks would impair defense capabilities, complicating crisis management during the very moment it’s most needed.

"Beyond the immediate blast and pulse, a space-based nuclear explosion would have a long-duration effect that could be even more damaging to space infrastructure. The explosion’s charged particles would become trapped by Earth’s magnetic field, forming an artificial radiation belt encircling the planet (Scientific American).

"This is exactly what happened after Starfish Prime: a man-made #RadiationBelt lingered for years, eventually destroying a third of all satellites in orbit at the time (Scientific American). In today’s environment, with thousands of satellites, the consequences would be dire. The intense radiation would bathe #LowEarthOrbit, causing surviving satellites to degrade and fail over the ensuing days, weeks, and months (Aerospace America). Many satellites that weren’t immediately destroyed would succumb to this enhanced radiation environment.

"Nearly 10,000 active satellites now orbit Earth, and most are not designed to withstand extreme nuclear radiation (Aerospace America). Critical constellations – for example, #SpaceX’s #Starlink network of small satellites (over 6,000 in orbit) that provides high-speed broadband, including to Ukrainian forces – would likely be heavily degraded or completely knocked offline (Scientific American). Replacement of satellites would be hampered as well: the orbital 'fallout' zone could remain dangerous for new satellites for years, denying space to any fresh deployments (Aerospace America). Even astronauts and cosmonauts in space could be in peril."

Read more:
https://ieu-monitoring.com/editorial/orbiting-armageddon-russias-emp-threat-from-space-and-transatlantic-responses/609700

Archived version:
https://archive.ph/PPMrQ

#NoNukesInSpace #LEO #KesslerEffect
#KesslerSyndrome #NoNukes #NoWar #NuclearWeapons #Satellites