Luna 10 (or Lunik 10) was a 1966 Soviet lunar

robotic spacecraft Uncrewed spacecraft or robotic spacecraft are spacecraft without people on board. Uncrewed spacecraft may have varying levels of autonomy from human input, such as remote control, or remote guidance. They may also be autonomous, in which t ...

mission in the

Luna program The Luna programme (from the Russian word " Luna" meaning "Moon"), occasionally called ''Lunik'' by western media, was a series of robotic spacecraft missions sent to the Moon by the Soviet Union between 1959 and 1976. The programme accompli ...

. It was the first

artificial satellite A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scienti ...

of the Moon, and any other body other than Earth and the Sun (in

heliocentric orbit A heliocentric orbit (also called circumsolar orbit) is an orbit around the barycenter of the Solar System, which is usually located within or very near the surface of the Sun. All planets, comets, and asteroids in the Solar System, and the Sun ...

). Luna 10 conducted extensive research in lunar orbit, gathering important data on the strength of the Moon's

magnetic field A magnetic field (sometimes called B-field) is a physical field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular ...

, its radiation belts, and the nature of lunar rocks (which were found to be comparable to terrestrial

basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...

rocks),

cosmic radiation Cosmic rays or astroparticles are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Sol ...

, and

micrometeoroid A micrometeoroid is a tiny meteoroid: a small particle of rock in space, usually weighing less than a gram. A micrometeorite is such a particle that survives passage through Earth's atmosphere and reaches Earth's surface. The term "micrometeoro ...

density. Perhaps its most important finding was the first evidence of mass concentrations (called "mascons") — areas of denser material below the lunar surface that distort lunar orbital trajectories.

The spacecraft

Part of the ''E-6S'' series, Luna 10 was battery powered and had an on-orbit dry mass of 540 kg. Scientific instruments included a gamma-ray

spectrometer A spectrometer () is a scientific instrument used to separate and measure Spectrum, spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomeno ...

for energies between 0.3–3 MeV (50–500 pJ), a triaxial

magnetometer A magnetometer is a device that measures magnetic field or magnetic dipole moment. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A compass is one such device, ...

, a

meteorite A meteorite is a rock (geology), rock that originated in outer space and has fallen to the surface of a planet or Natural satellite, moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical ...

detector, instruments for solar-plasma studies, and devices for measuring

infrared Infrared (IR; sometimes called infrared light) is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those ...

emissions from the Moon and radiation conditions of the lunar environment. Gravitational studies were also conducted.

The flight

Luna 10 launched towards the

Moon The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...

on 31 March 1966 at 10:48 GMT. After a midcourse correction on 1 April, the spacecraft entered lunar orbit on 3 April 1966 and completed its first orbit 3 hours later (on 4 April

Moscow Moscow is the Capital city, capital and List of cities and towns in Russia by population, largest city of Russia, standing on the Moskva (river), Moskva River in Central Russia. It has a population estimated at over 13 million residents with ...

time). A 245-kilogram instrument compartment separated from the main bus, which was in a 218 x 621 mile orbit inclined at 71.9° to the lunar equator. Luna 10 operated for 460 lunar orbits and performed 219 active data transmissions before radio signals were discontinued on 30 May 1966. The spacecraft eventually crashed on the moon on an unknown date.

The Internationale

The spacecraft carried a set of solid-state oscillators that had been programmed to reproduce the notes of "

The Internationale "The Internationale" is an international anthem that has been adopted as the anthem of various anarchist, communist, socialist, democratic socialist, and social democratic movements. It has been a standard of the socialist movement since ...

", so that it could be broadcast live to the 23rd Congress of the Communist Party of the Soviet Union. During a rehearsal on the night of 3 April, the playback went well, but the following morning, controllers discovered a missing note and played the previous night's tape to the assembled gathering at the Congress — claiming it was a live broadcast from the Moon. File:Luna 10 Space Probe.jpg, Replica of Luna 10 space probe, K. E. Tsiolkovsky Museum of the History of Cosmonautics File:Laika ac Memorial Museum of Astronautics (6995717351).jpg, Luna 10 model (suspended), Memorial Museum of Cosmonautics File:1966 CPA 3380.jpg, Stamp of the Luna 10

References

{{Moon spacecraft Luna programme Spacecraft launched in 1966 1966 in the Soviet Union Spacecraft launched by Molniya-M rockets Satellites orbiting the Moon Non Earth orbiting satellites of the Soviet Union