What Happened the Last Time a Nuke was Detonated in Space?
It went far worse than anyone planned.
Project Starfish
In 1962 the United States was about to execute the largest nuclear test in outer space, a joint effort of the Atomic Energy Commission (AEC) and the Defense Atomic Support Agency, known as Starfish Prime. The test was part of Operation Fishbowl, a series of tests in 1962 begun in response to the Soviet announcement on August 30, 1961, that they would end a three-year moratorium on testing. But what happened next was far worse than anyone could have imagined.
The Starfish test was originally planned as the second in the Fishbowl series, but the first launch (Bluegill) was lost by the radar tracking equipment and had to be destroyed in flight. The initial Starfish launch attempt on June 20 was also aborted in flight, this time due to failure of the Thor launch vehicle. The Thor missile flew a normal trajectory for 59 seconds; then the rocket engine stopped, and the missile began to break apart. The range safety officer ordered the destruction of the missile and warhead. Parts of the missile and some radioactive contamination fell upon Johnston Atoll and nearby Sand Island and the surrounding ocean.
The Chaos of Starfish Prime
On July 9, 1962, at 09:00:09 Coordinated Universal Time (11:00:09 pm on July 8, 1962, Honolulu time), the Starfish Prime test was detonated at an altitude of 250 miles (400 km). The actual weapon yield came very close to the design yield, which various sources have set at different values in the range of 1.4 to 1.45 Mt (5.9 to 6.1 PJ). The nuclear warhead detonated 13 minutes 41 seconds after liftoff of the Thor missile from Johnston Atoll.
But it was the aftermath of the explosion that would prove to be the most unexpected and destructive. Starfish Prime caused an electromagnetic pulse (EMP) that was far larger than expected, so much larger that it drove much of the instrumentation off scale, causing great difficulty in getting accurate measurements. The Starfish Prime electromagnetic pulse also made those effects known to the public by causing electrical damage in Hawaii, about 900 miles (1,450 km) away from the detonation point, knocking out about 300 streetlights, setting off numerous burglar alarms, and damaging a telephone company microwave link. The EMP damage to the microwave link shut down telephone calls from Kauai to the other Hawaiian islands.
An Unexpected Fireball
A total of 27 small rockets were launched from Johnston Atoll to obtain experimental data from the Starfish Prime detonation. In addition, a large number of rocket-borne instruments were launched from Barking Sands, Kauai, in the Hawaiian Islands. A large number of United States military ships and aircraft were operating in support of Starfish Prime in the Johnston Atoll area and across the nearby North Pacific region. A few military ships and aircraft were also positioned in the region of the South Pacific Ocean near the Samoan Islands. This location was at the southern end of the magnetic field line of the Earth’s magnetic field from the position of the nuclear detonation, an area known as the “southern conjugate region” for the test.
But the most significant aftermath of the test was the creation of a belt of MeV electrons, which were trapped by the Earth’s magnetic field, forming radiation belts that damaged or destroyed one-third of all satellites in low orbit, including the UK’s first orbital satellite, Ariel One.
What is Russia Planning?
This experience has raised concerns over recent reports of Russia developing a new space-based anti-satellite (ASAT) weapon, with a nuclear component.
The precise nature of this nuclear component is unclear, with theories suggesting Russia is developing either a nuclear-armed or nuclear-powered ASAT capability. A nuclear-armed ASAT weapon could permanently disable a large portion of an adversary’s satellites in one strike, while a nuclear-powered ASAT weapon utilizing lasers or particle beams could offer the same benefits without generating excessive space debris or radiation.
While Russia has the capability to deploy a space-based nuclear warhead, developing a sophisticated nuclear-propelled electromagnetic weapon system in space will be challenging. If an active weapon system is deployed in space, it would violate the 1967 Outer Space Treaty and provide Moscow with the option to launch a devastating attack on NATO at any moment, potentially preventing the bloc from reacting decisively against a land-attack on an alliance member. This threat may be what Russian President Vladimir Putin hopes to hang over the heads of the West.
