Luna 13 Date: 12.21.1966 Luna 13 became the second Soviet
spacecraft to successfully soft-land on the
surface of the Moon.
The probe landed in the
Ocean of Storms at 18:01 UT on 24 December
1966, between the Krafft and Seleucus
craters at 18°52' north latitude and 62°3'
west longitude. Unlike its predecessor,
the heavier Luna 13 lander (113 kilograms)
carried a suite of scientific instruments in
addition to the usual imaging system.
A
three-axis accelerometer within the pressurized
frame of the lander recorded the landing
forces during impact to determine the soil
structure down to a depth of 20 to 30 centimeters.
A pair of spring-loaded booms was
also deployed. Both were equipped with titanium-
tipped rods that were driven into the
ground with a powerful force by small explosive
charges to measure soil density (found at
roughly 0.8 grams per cubic centimeter). Four
radiometers recorded infrared radiation from
the surface indicating a noon temperature of
117 ± 3°C while a radiation detector indicated
that radiation levels would be less than
hazardous for humans.