Even before the "Sputnik 1" launch, Korolev was interested in getting to the Moon. He came up with the notion to modify the R-7 missile in order to carry a package to the Moon. However, it was not until 1958 that this idea was approved, after Korolev wrote a letter explaining that his current technology would make it possible to get to the Moon. A modified version of the R-7 launch vehicle was used with a new upper stage. The engine for this final stage was the first designed to be fired in outer space. "Mechta" is the Russian word meaning "dream", and this is the name Korolev called his moon ships. Officially, the Soviet Union called them Lunas. The first three lunar probes launched in 1958 all failed in part because of political pressure forcing the launches to be rushed with an inadequate budget to test and develop the hardware properly before they were ready to fly. Korolev thought political infighting in Moscow was responsible for the lack of sufficient funding for the program, although the US space program at this early phase also had a scarcely enviable launch record. Once, when pressured to beat the US to a working lunar probe, Korolev allegedly exclaimed: "Do you think that only American rockets explode!?" The Luna 1 mission on 2 January 1959 was intended to impact the surface, but missed by about . Nevertheless, this probe became the first to reach escape velocity and the first to go near the Moon, as well as becoming the first man-made object to enter the Sun's orbit. A subsequent attempt (Luna E-1A No.1) failed at launch, and then Luna 2 successfully impacted the surface on 14 September 1959, giving the Soviets another first. This was followed just one month later by an even greater success with Luna 3. It was launched only two years after Sputnik 1, and on 7 October 1959 was the first spacecraft to photograph the far side of the Moon, which was something the people of earth had never seen beforehand.