Russian President Vladimir Putin first mention of his country's brand new nuclear-powered cruise missile was during his state of the nation address on March 1, 2018. He showed an animated video showcasing the guided-missile flying over oceans, avoiding air defense systems, circumnavigating Cape Horn and ultimately hitting a target on the US island of Hawaii. RT, Russia's government-funded intentional broadcaster, referred to the new weapons system as 9M730 Burevestnik in a YouTube clip.

But observers have been left wondering whether the animated video presented by Putin and RT prove this cruise missile, named Skyfall by NATO,  actually exists.

Explosion may indicate missile tests

Last week, a severe explosion occurred at a Russian military facility in the Arkhangelsk region, according to the country's state-controlled nuclear energy corporation Rosatom. The agency said five staff members were killed when an accident occurred testing "a liquid propulsion system involving isotopes." Three other Rosatom employees suffered burns. 

The agency's statement raised a number of questions as most isotopes are radioactive and not ordinarily used as fuel for liquid-propelled rockets.

Following the incident, Russia's state weather agency, Roshydromet, said on Tuesday that it believed radiation levels had risen by four to 16 times in the area. Greenpeace said radiation levels rose by 20 times. Both of these figures would seem to suggest that radiation had indeed been emitted during the Arkhangelsk accident.

But as rockets propelled by liquid fuel do not emit any radiation, it is likely that the missile system tested in Arkhangelsk combines both conventional and nuclear propulsion systems. 

While Putin has insisted that the new cruise missile was successfully tested in 2017, there is no independent evidence supporting the president's statement. Indeed, US broadcaster CNBC in late March 2019 cited anonymous intelligence sources who said Russia's new cruise missiles had been tested five times since February 2018 but crashed each time. CNBC also said the missile had never flown further than 22 miles (17 kilometers).

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If the Burevestnik weapon exists it would be the world's first intercontinental cruise missile. This would make it strategically superior to intercontinental ballistic missiles (ICBMs), which follow a set trajectory after being launched, allowing them to be theoretically intercepted by missile defense systems.

In practice, however, ICBMs have appeared impossible to stop ever since the 1980s due to their great speed. US and Russian ICBMs can simultaneously deliver multiple nuclear warheads and overwhelm any air defense system.

How does a nuclear-powered propulsion system work?

A nuclear-powered rocket engine does not use energy generated through combustion to propel a missile forward. Instead, it does so by relying on heat generated through ongoing nuclear fission. Following World War II, both the United States and the Soviet Union unsuccessfully experimented with nuclear-powered aircraft and carrier rockets. 

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While both superpowers built and flew planes with nuclear reactors on board, these were never connected to the engines, and the planes relied on conventional jet engines instead. The trials were to observe whether the aircraft crew could be sufficiently shielded from the radiation emitted by the nuclear reactors. 

Radiation leakage is one of the major risks associated with nuclear-power missiles. While no aircraft crew is at risk of contamination, the crash of such a nuclear-powered missile could have a devastating effect. 

In the case of a nuclear war, there is a chance military leaders and engineers would accept the risk of a nuclear-missile unintentionally landing on an allied nation. The Archangelsk incident, however, may already show just how dangerous this technology could be even in times of peace.

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