Soviet and Russian Lunar Exploration

End of Lunokhod journey
October 1971
Exploration of large
crater, March 1971
Final operations, June - Sep 1971
Lunokhod resumes journey north, May 1971
Journey northward
Feb.1971
Luna 17 landing stage +J Return to landing stage, Jan 1971
Arrival, 17 Nov 1970
Journey southward Dec. 1970
Lunokhod's journey
Return route to landing
stage, Jan. 1971
recharging. Lunokhod travelled only 197 m in May, concentrating on static experiments.
The mooncar had appeared to be losing power and it was probably decided to
concentrate on less energy-demanding experiments (Lunokhod was never expected to
last more than six months).
Measurement of the strength of the lunar surface was an important aspect of
the work of Lunokhod. The vehicle would stop and the penetrating cone would be
lowered at the back of the vehicle. The penetrator, called PrOP, coned at an angle of
60°. First, it was forced into the surface to a depth of up to 5 cm to test force.
Some pressure was applied, equivalent to a sixth of the weight of the rover. Then
vanes inside the cone were rotated 90 ° for torque, again another measurement of
surface strength. This was done 500 times. The results of penetration and trafficability
tests were published in detail, finding that Lunokhod operated on surfaces that were