LUNA 3, or E-2A NO.1 was a Soviet spacecraft launched in 1959 as part
Luna programme . It was the first-ever mission to photograph
the far side of the
Moon . It was also the third space probe to be
sent to the neighborhood of the
Moon ,. Though it returned rather poor
pictures by later standards, the historic, never-before-seen views of
the far side of the
Moon caused excitement and interest when they were
published around the world, and a tentative Atlas of the Far Side of
Moon was created after image processing improved the pictures.
These views showed mountainous terrain, very different from the near
side, and only two dark, low-lying regions which were named Mare
Moscoviense (Sea of Moscow) and
Mare Desiderii (Sea of Desire). Mare
Desiderii was later found to be composed of a smaller mare, Mare
Ingenii (Sea of Ingenuity), and several other dark craters. The reason
for this difference between the two sides of the
Moon is still not
fully understood, but it seems that most of the dark lavas that flowed
out to produce the maria formed under the Earth-facing half.
Luna 3 was followed by the United States with
Ranger 7 ,
Ranger 8 ,
Ranger 9 .
* 1 Design
* 2 Mission
* 2.1 First gravity assist
* 3 Lunar photography
* 4 References
* 5 External links
The space probe was a cylindric canister with hemispheric ends and a
wide flange near the top. The probe was 130 cm long and 120 cm at its
maximum diameter at the flange. Most of the cylindric section was
roughly 95 cm in diameter. The canister was hermetically sealed and
pressurized to about 0.22 atmosphere (23 kilopascals ). Several solar
cells were mounted on the outside of the cylinder, and these provided
electric power to the storage batteries inside the space probe.
Shutters for thermal control were positioned along the cylinder and
opened to expose a radiating surface when the internal temperature
exceeded 25 °C. The upper hemisphere of the probe held the covered
opening for the cameras. Four antennas protruded from the top of the
probe and two from its bottom. Other scientific equipment was mounted
on the outside, including micrometeoroid and cosmic ray detectors, and
the Yenisey-2 imaging system. The gas jets for its attitude control
system were mounted on the lower end of the spacecraft. Several
photoelectric cells helped maintain orientation with respect to the
Sun and the Moon.
There were no rocket motors for course corrections.
Its interior held the cameras and the photographic film processing
system, radio transmitter , storage batteries , gyroscopic units , and
circulating fans for temperature control. It was spin-stabilized for
most of its flight, but its three-axis attitude control system was
activated while taking photos.
Luna 3 was radio-controlled from ground
stations in the Soviet Union.
USSR stamp commemorating first photographs of the Far side
After launching on an Luna 8K72 (number I1-8) rocket over the North
Pole , the Blok-E escape stage was shut down by radio control to put
Luna 3 on its course to the Moon. Initial radio contact showed that
the signal from the space probe was only about one-half as strong as
expected, and the internal temperature was rising. The spacecraft spin
axis was reoriented and some equipment was shut down, resulting in a
temperature drop from 40 °C to about 30 °C. At a distance of 60,000
to 70,000 km from the Moon, the orientation system was turned on and
the spacecraft rotation was stopped. The lower end of the craft was
pointed at the Sun, which was shining on the far side of the Moon.
The space probe passed within 6,200 km of the
Moon near its south
pole at the closest lunar approach at 14:16 UT on 6 October 1959, and
continued on over the far side. On 7 October, the photocell on the
upper end of the space probe detected the sunlit far side of the Moon,
and the photography sequence was started. The first picture was taken
at 03:30 UT at a distance of 63,500 km from the Moon, and the last
picture was taken 40 minutes later from a distance of 66,700 km.
A total of 29 pictures were taken, covering 70% of the far side.
After the photography was complete the spacecraft resumed spinning,
passed over the north pole of the
Moon and returned towards the Earth.
Attempts to transmit the pictures to the
Soviet Union began on October
8 but the early attempts were unsuccessful due to the low signal
Luna 3 drew closer to the Earth, a total of about 17
viewable but poor quality photographs were transmitted by the 18th of
October. All contact with the probe was lost on 22 October 1959. The
space probe was believed to have burned up in the Earth's atmosphere
in March or April 1960. Another possibility was that it might have
survived in orbit until 1962 or later.
FIRST GRAVITY ASSIST
Luna 3 trajectory and the gravity assist maneuver Main
Gravity assist § Historical origins of the method
The gravity assist maneuver was first used in 1959 when Luna 3
photographed the far side of Earth's Moon. After launch from the
Baikonur Cosmodrome ,
Luna 3 passed behind the
Moon from south to
north and headed back to Earth. The gravity of the
Moon changed the
spacecraft's orbit; also, because of the Moon's own orbital motion,
the spacecraft's orbital plane was also changed. The return orbit was
calculated so that the spacecraft passed again over the Northern
hemisphere where the Soviet ground stations were located. The maneuver
relied on research performed under the direction of Mstislav Keldysh
Steklov Institute of Mathematics .
Luna 3 phototelegraph system at Tsiolkovsky State Museum of the
History of Cosmonautics The first image returned by Luna 3
showed the far side of the
Moon was very different from the near side,
most noticeably in its lack of lunar maria (the dark areas)
The purpose of this experiment was to obtain photographs of the lunar
surface as the spacecraft flew by the Moon. The imaging system was
designated Yenisey-2 and consisted of a dual-lens camera AFA-E1, an
automatic film processing unit, and a scanner. The lenses on the
camera were a 200 mm focal length, f /5.6 aperture objective and a 500
mm, f/9.5 objective . The camera carried 40 frames of temperature- and
radiation-resistant 35 mm isochrome film . The 200 mm objective could
image the full disk of the
Moon and the 500 mm could take an image of
a region on the surface. The camera was fixed in the spacecraft and
pointing was achieved by rotating the craft itself.
Luna 3 was the first successful three-axis stabilized spacecraft.
During most of the mission, the spacecraft was spin stabilized, but
for photography of the Moon, the spacecraft oriented one axis toward
the Sun and then a photocell was used to detect the
Moon and orient
the cameras towards it. Detection of the
Moon signaled the camera
cover to open and the photography sequence to start automatically. The
images alternated between both cameras during the sequence. After
photography was complete, the film was moved to an on-board processor
where it was developed, fixed, and dried. Commands from the Earth were
then given to move the film into a flying spot scanner where a spot
produced by a cathode ray tube was projected through the film onto a
photoelectric multiplier . The spot was scanned across the film and
the photomultiplier converted the intensity of the light passing
through the film into an electric signal which was transmitted to the
Earth (via frequency-modulated analog video, similar to a facsimile).
A frame could be scanned with a resolution of 1000 (horizontal) lines
and the transmission could be done at a slow-scan television rate at
large distances from the Earth and a faster rate at closer ranges.
The camera took 29 pictures over 40 minutes on 7 October 1959, from
03:30 UT to 04:10 UT at distances ranging from 63,500 km to 66,700 km
above the surface, covering 70% of the lunar far side. Seventeen (some
say twelve) of these frames were successfully transmitted back to the
Earth (tracking stations in Crimea and Kamchatka), and six were
published (frames numbered 26, 28, 29, 31, 32, and 35). They were
humankind's first views of the far hemisphere of the Moon.
The imaging system was developed by P.F. Bratslavets and I.A.
Rosselevich at the Leningrad Scientific Research Institute for
Television and the returned images were processed and analyzed by
Iu.N. Lipskii and his team at the Sternberg Astronomical Institute.
The camera AFA-E1 was developed and manufactured by the KMZ factory
(Krasnogorskiy Mekhanicheskiy Zavod ).
The film, temperature-resistant and radiation-hardened, came from
American Genetrix balloons which had been recovered by the Soviets.
* ^ McDowell, Jonathan. "Launch Log". Jonathan's Space Page.
Retrieved 14 December 2014.
* ^ McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page.
Retrieved 14 December 2014.
* ^ A B "Exploring the