Luna 2 (E-1A series) or Lunik 2 was the second of the Soviet Union’s Luna programme spacecraft launched to the Moon. It was the first spacecraft to reach the surface of the Moon, and the first man-made object to land on another celestial body. On September 14, 1959, it successfully impacted east of Mare Imbrium near the craters Aristides, Archimedes, and Autolycus.
Launch was scheduled for September 9, but the Blok I core stage was shut down after it failed to reach full thrust at ignition. The booster was removed from the pad and replaced by a different vehicle, delaying the flight by three days. Luna 2, like Luna 1, took a direct path to the Moon, a journey of around 36 hours. The Earth-Moon gravitational system forced it to follow a curved trajectory, and launch had to occur from the side of the Earth opposite the Moon. Luna 2 hit the Moon about 800 kilometres from the centre of the visible disk on 1959 September 14 at 21:02:24.
Luna 2 was similar in design to Luna 1, a spherical spacecraft with protruding antennas and instrument parts. The instrumentation was also similar to Luna 1, including scintillation counters, geiger counters, a magnetometer, Cherenkov detectors, and micrometeorite detectors. There were no propulsion systems on Luna 2 itself.
Once Luna 2 was split from its upper stage it started transmitting information back to earth using three different transmitters. These transmitters were providing precise information on its course allowing scientist to calculate that Luna 2 would hit its mark on the moon around 0005 on September 14. In order to be able to get a visual of Luna 2 from Earth on September 13 it released a vapor cloud that would expand into a 650 km diameter that would be seen by observatories in Alma Ata,Byurakan, Abastuma, Tbilisi, and Stalinabad. This vapor cloud also acted as an experiment to see how the sodium gas would act in a vacuum and zero gravity.
The last stage of the rocket that carried Luna 2 did not carry any type of tracking device so there was uncertainty as to where it landed, but it did hit the Moon surface about 30 minutes after Luna 2 hit.