Scientists Launch a Research Rocket. Russia Opens the Nuclear Briefcase.

The rocket was scientific. That was not immediately obvious to the radar watching it.

On Wednesday morning, 25 January 1995, Norwegian and American researchers launched a four-stage Black Brant XII sounding rocket from Andøya in northern Norway.

Its mission was peaceful: carry instruments high above Earth to investigate the aurora.

Norway had notified neighbouring countries of a scientific launch campaign covering a window from 15 January to 10 February.

Somewhere between diplomatic notification and operational awareness, that reassurance failed.

Russian early-warning radar detected the rocket climbing rapidly from the Norwegian coast.

The trajectory demanded attention.

At the beginning of flight, a civilian research rocket and a submarine-launched ballistic missile could look disturbingly similar. Russian personnel also had to consider a theoretical attack in which a single high-altitude nuclear detonation disrupted radar before a larger strike.

The alert moved upward through the Russian command system.

Within minutes, President Boris Yeltsin and senior military commanders were using the Cheget nuclear-command communications system to monitor the object. Yeltsin later said that this was the first time he had activated his nuclear briefcase during a real alert.

For several minutes, officials tracked the rocket and evaluated what they were seeing.

Then its trajectory supplied the crucial answer.

The object was not heading toward Russia.

The alert ended without a Russian launch order. The Black Brant continued its scientific mission and eventually fell into the sea.

Popular retellings sometimes compress the incident into a weather rocket almost starting World War III.

That is too certain.

The documented sequence was a genuine nuclear-command alert, but available evidence does not show that Russia had committed to retaliation or that nuclear war had become inevitable.

The event is strange enough without the embellishment.

A publicly announced experiment designed to study lights in the upper atmosphere entered Russia's nuclear-warning chain because the people operating that chain could not initially know whether the object on their screens carried scientific instruments or something very different.

The aurora experiment worked.

So, fortunately, did the part where everyone waited long enough to identify it.