The Luna programme
The Luna programme ("Luna" meaning "Moon"),
occasionally called Lunik or Lunnik, was a series of robotic
spacecraft missions sent to the Moon by the Soviet Union between
1959 and 1976. Fifteen were successful, each designed as either an
orbiter or lander, and accomplished many firsts in space
exploration. They also performed many experiments, studying the
Moon´s chemical composition, gravity, temperature, and radiation.
Twenty-four spacecraft were formally given the Luna designation,
although more were launched. Those that failed to reach orbit were
not publicly acknowledged at the time, and not assigned a Luna
number. Those that failed in low Earth orbit were usually given
Cosmos designations. The estimated cost of Luna Program was about
$4.5 billion.
Luna 1 missed its intended impact with the Moon
and became the first spacecraft to fall into orbit around the
Sun.
In 1959, the Luna 2 mission successfully
impacted upon the lunar surface, becoming the first man-made object
to reach the Moon.
Luna 3 rounded the Moon later that year, and
returned the first photographs of its far side, which can never be
seen from Earth.
Luna 9 became the first probe to achieve a soft
landing on another planetary body (February 1966). It returned five
black and white stereoscopic circular panoramas, which were the
first close-up shots of the Lunar surface.
Later that year Luna 10 became the first
artificial satellite of the Moon.
Luna 17 and Luna 21 carried vehicles that roamed
around on the Moon´s terrain (see Lunokhod programme).
Another major achievement of the Luna programme,
with the Luna 16, Luna 20 and Luna 24 spacecraft, was the ability
to collect samples of lunar soil and return them to Earth, by 1970.
The program returned 0.326 kg of lunar samples. The Luna missions
were the first space-exploration sample return missions to rely
solely on advanced robotics.
Luna 20
Luna 20 (Ye-8-5 series) was the second of three
successful Soviet lunar sample return missions. It was flown as
part of the Luna program, also called Lunik 20, as a robotic
competitor to the six successful Apollo lunar sample return
missions. Luna 20 was placed in an intermediate Earth parking orbit
and from this orbit was sent towards the Moon. It entered lunar
orbit on February 18, 1972. On February 21, 1972, Luna 20 soft
landed on the Moon in a mountainous area known as the Apollonius
highlands near Mare Fecunditatis (Sea of Fertility), 120 km from
where Luna 16 had landed. While on the lunar surface, the panoramic
television system was operated. Lunar samples were obtained by
means of an extendable drilling apparatus. The ascent stage of Luna
20 was launched from the lunar surface on 22 February 1972 carrying
55 grams of collected lunar samples in a sealed capsule. It landed
in the Soviet Union on 25 February 1972. The lunar samples were
recovered the following day.
This was the eighth Soviet spacecraft launched
to return lunar soil to Earth. It was evidently sent to complete
the mission that Luna 18 had failed to accomplish. After a 4.5-day
flight to the Moon, which included a single midcourse correction on
15 February, Luna 20 entered orbit around the Moon on 18 February.
Initial orbital parameters were 100 x 100 kilometers at 65°
inclination. Three days later, at 19:13 UT, the spacecraft fired
its main engine for 267 seconds to begin descent to the lunar
surface. A second firing further reduced velocity before Luna 20
set down safely on the Moon at 19:19 UT on 21 February 1972 at
coordinates 3°32´ north latitude and 56°33´ east longitude, only
1.8 kilometers from the crash site of Luna 18. After collecting a
small sample of lunar soil, the spacecraft’s ascent stage
lifted off at 22:58 UT on 22 February and quickly accelerated to
2.7 kilometers per second velocity—sufficient to return to
Earth. The small spherical capsule eventually parachuted down
safely on an island in the Karkingir River, 40 kilometers north of
the town of Jezkazgan in Kazakhstan, at 19:19 UT on 25 February
1972.Lunar
Mission Sample
Returned Year
Luna 16 101 g 1970
Luna 20 55 g 1972
Luna 24 170 g 1976
The 55-gram soil sample differed from that
collected by Luna 16 in that the majority (50 to 60 %) of the rock
particles in the newer sample were ancient lunar highlands
anorthosite (which consists largely of feldspar) rather than the
basalt of the earlier one (which contained about 1 to 2 % of
anorthosite). The American Apollo 16 mission returned similar
highlands material two months later. Like the Luna 16 soil, samples
of the Luna 20 collection were shared with American and French
scientists.
In March 2010, NASA reported that the Lunar
Reconnaissance Orbiter had spotted the Luna 20.
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