The first two flights of the Vanguard program, designated Vanguard TV-0 and Vanguard TV-1, were actually the last two remaining RTV-N-12a Viking rockets modified. Vanguard TV-0, launched on 8 December 1956, primarily tested new telemetry systems, while Vanguard TV-1 on 1 May 1957, was a two-stage vehicle testing separation and ignition of the solid-fueled upper stage of Vanguard. Vanguard TV-2, launched on 23 October 1957, after several abortive attempts, was the first real Vanguard rocket. The second and third stages were inert, but the flight successfully tested first/second-stage separation and spin-up of the third stage. However, by that time, the Soviet Union had already placed the Sputnik 1 satellite into orbit, and so project Vanguard was more or less forced to launch its own satellite as soon as possible. Therefore, a very small experimental satellite (derisively called the "grapefruit" by Nikita Khrushchev, and weighing only ) was added to Vanguard TV-3, which was to be the first test of an all-up Vanguard rocket. Although the NRL and Glenn L. Martin Company tried to emphasize that the Vanguard TV-3 mission was a pure test flight (and one with several "firsts"), everyone else saw it as the first satellite launch of the Western world, billed as "America's answer to Sputnik". Wernher von Braun angrily said about the Sputnik launch: "We knew they were going to do it. Vanguard will never make it. We have the hardware on the shelf. We can put up a satellite in 60 days".