The Complete Book of Spaceflight: From Apollo 1 to Zero Gravity

the crew of Apollo 8 entered lunar orbit and the
record books.
There was to be a chilling postscript. The following
month, the delayed Proton was rolled out to its pad
for with an unmanned L-1: there would be no risking
a human passenger now that the race to circle the
Moon first was over. The rocket took off and, as its
second stage ignited, blew up. The launch escape system
also failed, putting it beyond all doubt that had
a cosmonaut been on board, he would have been
killed.
Zond Statistics
Zond 7 and 8
Three weeks after Apollo 11 touched down on the
lunar surface, Zond flights resumed. Zond 7 looped
around the Moon, sent back the first color photographs
of the Moon by a Soviet spacecraft, and executed
a perfect entry and landing to become the first
totally successful flight of the L-1 program. A little over
a year later, Zond 8 became the last of its kind, ending
its circumlunar foray with a single rather than the
planned double reentry. (See table, “Zond Statistics.”)
Launch
Zond Date Vehicle Mass (kg) Notes
1 Apr. 2, 1964 Molniya 890 Venus flyby, contact lost en route
2 Nov. 30, 1964 Molniya 890 Mars flyby, contact lost en route
3 Jul. 18, 1965 Molniya 959 Lunar flyby, continued into solar orbit
4 Mar. 2, 1968 Proton 5,390 Circumlunar; destroyed during reentry
5 Sep. 15, 1968 Proton 5,390 Circumlunar; returned Sep. 21, 1968
6 Nov. 10, 1968 Proton 5,375 Circumlunar; returned Nov. 17, 1968
7 Aug. 7, 1969 Proton 5,975 Circumlunar; returned Aug. 14, 1969
8 Oct. 20, 1970 Proton 5,375 Circumlunar; returned Oct. 27, 1970
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