In 1962, the US detonated a 1.4-megaton nuclear bomb in space that knocked out streetlights and triggered burglar alarms in Hawaii. 64 years later, it says weapons are already in orbit

Sixty-four years ago, the United States detonated one of the most powerful nuclear weapons ever used in an experiment far above Earth.On July 9, 1962, a 1.4-megaton thermonuclear bomb exploded roughly 400 kilometres above the Pacific Ocean in a test known as Starfish Prime. The blast created artificial auroras, produced a powerful electromagnetic pulse and injected huge amounts of energetic particles into Earth's magnetic field, creating an artificial radiation belt that damaged satellites.

Now, in 2026, the US has made another extraordinary admission about warfare beyond Earth.

For the first time, a senior US official has publicly acknowledged that the country has space-control weapons already deployed in orbit. US Air Force Secretary Troy Meink made the disclosure on September 14 at the Air, Space and Cyber Conference near Washington. “The United States now has on-orbit space control weapons capable of defending the joint force against hostile adversary action,” Meink said.


The Pentagon has not said what these weapons are, when they were deployed or exactly what they can do. Meink later said the wording of his announcement was deliberate but declined to provide further details.

That uncertainty may be the most intriguing part of the announcement.

What exactly is a space weapon?

The US military has not revealed what kind of space weapons it has. Experts have suggested that the weapons could include electronic-warfare systems such as satellite jammers. Such a weapon could interfere with signals without physically destroying another spacecraft and therefore avoid creating a cloud of dangerous orbital debris.

More destructive possibilities include kinetic systems capable of physically striking another spacecraft. There is also another category: spacecraft designed to maneuver close to another satellite, inspect it or potentially interfere with it. But none of these possibilities has been confirmed as the weapon Meink was referring to.

The strange connection to a 1962 nuclear explosion

Incidentally, this is not the first time that the country has tried to put weapons in space. On July 9, 1962, during a tense period of the Cold War, the United States detonated a 1.4-megaton thermonuclear bomb approximately 400 kilometers above Earth in an experiment called Starfish Prime. It was part of Operation Fishbowl, a series of high-altitude nuclear explosions conducted by the US in 1962.

The idea was not simply to create a spectacular explosion. Scientists and military planners wanted to understand how nuclear detonations behaved at extreme altitudes and what effects they could have on satellites, communications and Earth's space environment.

The result was unlike anything a conventional explosion on Earth would produce. There was no familiar mushroom cloud. Instead, the enormous release of energy interacted with Earth's magnetic field and upper atmosphere. Brilliant artificial auroras appeared across parts of the Pacific. But the most consequential effects were largely invisible.

A nuclear blast created an artificial radiation belt

Starfish Prime injected enormous numbers of energetic electrons into Earth's magnetosphere. These particles became trapped by Earth's magnetic field, producing an artificial radiation belt.

NASA records that the resulting radiation environment severely affected spacecraft. The Telstar communications satellite, launched just one day after the explosion, was exposed to radiation from the artificial belt at levels far beyond what its designers had expected. Several satellites subsequently suffered failures linked primarily to solar-cell damage.

The experiment therefore revealed something the military could not easily ignore: A nuclear weapon detonated in space would not simply destroy an enemy target. It could damage satellites indiscriminately. That included satellites belonging to the country that launched the weapon.

The blast also affected Hawaii

Starfish Prime was detonated hundreds of kilometres above the Pacific, yet its effects were felt much closer to Earth. The explosion generated a powerful electromagnetic pulse.

In Hawaii, roughly 1,400 kilometres away, the EMP caused electrical and communications disruptions, including failures of streetlights and activation of burglar alarms. The event demonstrated that a nuclear explosion in space could produce consequences over enormous distances without a conventional blast wave reaching the ground.

In 1962, there were only a few satellites. Today, almost everything depends on them

When Starfish Prime exploded, the Space Age was barely five years old. There were only a relatively small number of satellites around Earth. Today, the orbital environment is vastly more crowded and vastly more important.

Satellites support navigation, communications, weather forecasting, television, internet connectivity, financial systems, aviation, military operations and disaster response. That makes space infrastructure a strategic vulnerability.

A weapon that disables a satellite does not necessarily need to create a spectacular explosion to have a major effect. It could simply prevent a satellite from communicating.

It could interfere with its sensors. It could disrupt navigation signals. Or it could force an adversary to move or abandon an important spacecraft.

This is why modern space warfare increasingly focuses on counter-space capabilities rather than simply imagining missiles blowing up satellites.

The US says China and Russia are part of the reason

Washington's admission comes as the US, China and Russia develop increasingly sophisticated capabilities for operating in and potentially interfering with space.

US officials have repeatedly raised concerns about Russian and Chinese space capabilities, including maneuverable satellites and anti-satellite technologies.

China and Russia, meanwhile, have their own military space programmes and have demonstrated capabilities that have raised concerns in Washington.

Meink framed the US approach as a response to this changing environment, arguing that the country needs to be able to protect its military and economic interests in space.