V2 Rocket

From Turtledove

The Vergeltungswaffe 2 (V2) Rocket was an early ballistic missile developed by the Germans in the 1940s. The Germans used them in 1943 and 1944 against the Race's Conquest Fleet and successfully destroyed several of the Race's star ships on the ground. Although the Race was able to destroy these missiles with anti-missiles during the early stages of the war, it became vulnerable once these weapons were depleted and it was unable to manufacture more on its own immediately. The United States deployed a similar weapon designed by Robert Goddard against the Lizards in 1944.