Luna 13 was the third successful spacecraft to conduct a moon landing on 24th December 1966.
Its weight is 113 kilograms and it carried multiple scientific instruments and an imaging system. Images sent from Lunar 13 were five panoramas of the lunar surface.
One of its instruments was a pair of spring-loaded booms. One boom carried a penetrometer, designed to measure the force required to penetrate the lunar regolith; the penetrating force being supplied by a minute explosive charge. The other boom carried a backscatter densitometer to infer the density of the near-surface regolith.
Read more at Wikipedia Luna 13.