On 21 November a new Russian weapon hit the Ukrainian city of Dnipro, with 36 projectiles descending at high velocity like meteors through the clouds. Russia’s president Vladimir Putin said this was the first test of a new ballistic missile called Oreshnik and that more would follow.

Ukraine is seeking ways to neutralise the threat. While it has stopped other Russian attacks, including short-range ballistic missiles, this one will be more challenging. Like…