Circumlunar Missions
Main articles: Soyuz 7K-L1 and Moon Race#Soviet circumlunar loop flights (1967–1970)The missions 4 through 8 were test flights under for the Soviet Moonshot during the Moon race. The Soyuz 7K-L1 (also mentioned just as L1) spacecraft was used for the moon-aimed missions, stripped down to make it possible to launch around the moon from the Earth. They were launched on the Proton rocket which was just powerful enough to send the Zond on a free return trajectory around the moon without going into lunar orbit (the same path that Apollo 13 flew in its emergency abort). With minor modification, Zond was capable of carrying two cosmonauts.
In the beginning there were serious reliability problems with both the new Proton rocket and the similar new Soyuz spacecraft, but the test flights pressed ahead with some glitches. Then majority of tests flights from 1967–1970 (Zond 4 to Zond 8) showed problems during re-entry.
Zond spacecraft made only unmanned automatic flights. Four of these suffered malfunctions that would have injured or killed any crew. Instrumentation flown on these missions gathered data on micrometeor flux, solar and cosmic rays, magnetic fields, radio emissions, and solar wind. Many photographs were taken and biological payloads were also flown.
Read more about this topic: Zond Program
Famous quotes containing the word missions:
“There was only one catch and that was Catch-22, which specified that a concern for one’s own safety in the face of dangers that were real and immediate was the process of a rational mind.... Orr would be crazy to fly more missions and sane if he didn’t, but if he was sane he had to fly them. If he flew them he was crazy and didn’t have to; but if he didn’t want to he was sane and had to.”
—Joseph Heller (b. 1923)