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16 Scientific Instrument Technology of Lunar Lander
Surveyor 6 was launched in Nov. 1967. The mission objectives and instruments
onboard were identical to Surveyor 5. With another mirror, the TV camera could
observe lunar surface under the lunar lander. The original mirror was modified to
help the TV camera to take pictures in 360° azimuth and –60°~90° pitch. The camera
returned 29952 images. The powered lift-off experiment was conducted by Surveyor
6 on lunar surface. Three vernier engines were fired for 2.5 s, causing Surveyor 7
to lift off the lunar surface about 4 meters and land about 2.5 meters west of its
original position. Viewing of the original landing site by camera provided further
acknowledgement for mechanical properties of lunar soil. The results of the experiments showed that the surface had a basaltic composition, similar to that found at
the Surveyor 5 landing site.
Surveyor 7 was launched in Jan. 1968. The mission objectives were to acquire
images of different terrain and conduct measurement of lunar soil. The instruments
onboard were identical to Surveyor 6. The probe returned 21,274 images. The lunar
surface sampler conducted multiple digging experiments, over 16 measurement of
bearing strength, 7 digging trenches and 2 impacts. The α scattering instrument
investigated 3 lunar samples, undisturbed lunar surface, one rock and one new trench.
The TV camera recorded laser beam emitted from Earth observatory for two times. As
the target, the Surveyor 7 lander also successfully detected laser beams transmitted
from Earth to conduct precise measurement of Earth-Moon distance for the first time.
16.2.2 Instruments on Luna Probes and Major Achievements
From 1966 to 1976, there were 6 successful robotic lunar landers launched by the
Soviet Union, including luna 9, luna 16, luna 17, luna 20, luna 21 and luna 24.
Luna 9 was launched in Jan. 1966, and was the first spacecraft to achieve a lunar
soft landing. The mission objectives were to demonstrate lunar landing technology
and explore lunar surface environment. The instruments onboard included TV camera
and radiometer. The TV camera acquired panorama images of landing site by rotation
in azimuth and pitch. Luna 9 transmitted three series of TV pictures under different
illumination conditions back to Earth. The radiation dose by the radiometer was
0.3 mGy (1 Gy = 1 J/kg). The Luna 9 proved that the lunar surface could support
the weight of a lunar lander and an object would not sink on lunar surface.
The Luna 13 was launched in Dec. 1966, and its shape was similar to Luna 9. The
mission objectives were to demonstrate lunar landing technology and explore lunar
surface environment furthermore. The instruments onboard included TV camera, soil
penetrometer, radiation densitometer, backscatter densitometer, three-axis accelerator and infrared radiometer. The TV camera took five panorama images. The soil
penetrometer was applied to measure mechanical properties of lunar soil. The radiation densitometer was applied to measure cosmic radiation reflected by lunar surface.
The three-axis accelerator was applied to measure impact and stroke when the probe
was landing on lunar surface and the measurement results indicated that the Luna
13 sunk down to a depth of 20–30 cm. The backscatter densitometer was applied to
16 Scientific Instrument Technology of Lunar Lander
Surveyor 6 was launched in Nov. 1967. The mission objectives and instruments
onboard were identical to Surveyor 5. With another mirror, the TV camera could
observe lunar surface under the lunar lander. The original mirror was modified to
help the TV camera to take pictures in 360° azimuth and –60°~90° pitch. The camera
returned 29952 images. The powered lift-off experiment was conducted by Surveyor
6 on lunar surface. Three vernier engines were fired for 2.5 s, causing Surveyor 7
to lift off the lunar surface about 4 meters and land about 2.5 meters west of its
original position. Viewing of the original landing site by camera provided further
acknowledgement for mechanical properties of lunar soil. The results of the experiments showed that the surface had a basaltic composition, similar to that found at
the Surveyor 5 landing site.
Surveyor 7 was launched in Jan. 1968. The mission objectives were to acquire
images of different terrain and conduct measurement of lunar soil. The instruments
onboard were identical to Surveyor 6. The probe returned 21,274 images. The lunar
surface sampler conducted multiple digging experiments, over 16 measurement of
bearing strength, 7 digging trenches and 2 impacts. The α scattering instrument
investigated 3 lunar samples, undisturbed lunar surface, one rock and one new trench.
The TV camera recorded laser beam emitted from Earth observatory for two times. As
the target, the Surveyor 7 lander also successfully detected laser beams transmitted
from Earth to conduct precise measurement of Earth-Moon distance for the first time.
16.2.2 Instruments on Luna Probes and Major Achievements
From 1966 to 1976, there were 6 successful robotic lunar landers launched by the
Soviet Union, including luna 9, luna 16, luna 17, luna 20, luna 21 and luna 24.
Luna 9 was launched in Jan. 1966, and was the first spacecraft to achieve a lunar
soft landing. The mission objectives were to demonstrate lunar landing technology
and explore lunar surface environment. The instruments onboard included TV camera
and radiometer. The TV camera acquired panorama images of landing site by rotation
in azimuth and pitch. Luna 9 transmitted three series of TV pictures under different
illumination conditions back to Earth. The radiation dose by the radiometer was
0.3 mGy (1 Gy = 1 J/kg). The Luna 9 proved that the lunar surface could support
the weight of a lunar lander and an object would not sink on lunar surface.
The Luna 13 was launched in Dec. 1966, and its shape was similar to Luna 9. The
mission objectives were to demonstrate lunar landing technology and explore lunar
surface environment furthermore. The instruments onboard included TV camera, soil
penetrometer, radiation densitometer, backscatter densitometer, three-axis accelerator and infrared radiometer. The TV camera took five panorama images. The soil
penetrometer was applied to measure mechanical properties of lunar soil. The radiation densitometer was applied to measure cosmic radiation reflected by lunar surface.
The three-axis accelerator was applied to measure impact and stroke when the probe
was landing on lunar surface and the measurement results indicated that the Luna
13 sunk down to a depth of 20–30 cm. The backscatter densitometer was applied to