1.1 Significance of and General Approaches to Lunar Exploration
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technology and space application to be more open, which will prompt international
cooperation among China and other international parties in space domain.
1.1.2 General Approaches to Lunar Exploration
There are various approaches to explore the Moon along with development of space
technology and growing requirements of exploration. To date, there had been various
approaches to explore the Moon including flyby, impact, orbiting, soft-landing,
sample and return, manned lunar mission. Generally we called spacecraft to the
Moon ‘Probe’ compared to the man-made Earth satellite.
1. Flyby
Flyby the Moon means that the probe passes through the Moon at a distance from
thousands to ten thousand kilometers. While flying by the Moon, the probe took
photo or explored the environment. Usually the operation time was short and the
accuracy was low for a lunar flyby mission. At the beginning of lunar exploration
era 1960s, flyby was used because of the limit of space technology. For example, the
very first photo of lunar far side was taken by the Soviet Union Luna 3 probe when
flying by the far side of the Moon.
2. Impact
Impact is also called hard landing, which means that the probe impacts lunar surface
at high speed without deceleration. Sometimes there might be a special impact probe
onboard the lunar spacecraft. In the early stage, the probe impacted lunar surface in
order to acquire high resolution image and environment data when approaching, as
well as observe the matter due to the impact on the Earth or by the orbiter around
the Moon. Recently, some special impact probes were developed to generate the
moonquake in order to explore the internal structure of the Moon by detecting the
propagation of the moonquake wave. Some impact probes might even penetrate lunar
surface to study lunar interior geology, mechanics and thermal properties. It is hard
to penetrate into the Moon interior so that no such mission has been accomplished
up to date.
3. Orbiting
When the probe approaches the Moon, the velocity relative to the Moon is decelerated
by propulsion system to make it captured by the Moon gravity, and then the probe
will orbit around the Moon in circle or ellipse. Such probe is also called an orbiter.
An orbiter can cover large area of lunar surface during long life cycle around the
Moon, so remote sensing in visible light and multiple spectrum and exploration of
space environment near the Moon can be implemented. Global survey of the Moon
can be accomplished by the lunar orbiter, which makes it a common approach for
lunar reconnaissance survey. Now the Soviet Union, the United States of America
and China have successfully implemented lunar orbiting exploration.
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technology and space application to be more open, which will prompt international
cooperation among China and other international parties in space domain.
1.1.2 General Approaches to Lunar Exploration
There are various approaches to explore the Moon along with development of space
technology and growing requirements of exploration. To date, there had been various
approaches to explore the Moon including flyby, impact, orbiting, soft-landing,
sample and return, manned lunar mission. Generally we called spacecraft to the
Moon ‘Probe’ compared to the man-made Earth satellite.
1. Flyby
Flyby the Moon means that the probe passes through the Moon at a distance from
thousands to ten thousand kilometers. While flying by the Moon, the probe took
photo or explored the environment. Usually the operation time was short and the
accuracy was low for a lunar flyby mission. At the beginning of lunar exploration
era 1960s, flyby was used because of the limit of space technology. For example, the
very first photo of lunar far side was taken by the Soviet Union Luna 3 probe when
flying by the far side of the Moon.
2. Impact
Impact is also called hard landing, which means that the probe impacts lunar surface
at high speed without deceleration. Sometimes there might be a special impact probe
onboard the lunar spacecraft. In the early stage, the probe impacted lunar surface in
order to acquire high resolution image and environment data when approaching, as
well as observe the matter due to the impact on the Earth or by the orbiter around
the Moon. Recently, some special impact probes were developed to generate the
moonquake in order to explore the internal structure of the Moon by detecting the
propagation of the moonquake wave. Some impact probes might even penetrate lunar
surface to study lunar interior geology, mechanics and thermal properties. It is hard
to penetrate into the Moon interior so that no such mission has been accomplished
up to date.
3. Orbiting
When the probe approaches the Moon, the velocity relative to the Moon is decelerated
by propulsion system to make it captured by the Moon gravity, and then the probe
will orbit around the Moon in circle or ellipse. Such probe is also called an orbiter.
An orbiter can cover large area of lunar surface during long life cycle around the
Moon, so remote sensing in visible light and multiple spectrum and exploration of
space environment near the Moon can be implemented. Global survey of the Moon
can be accomplished by the lunar orbiter, which makes it a common approach for
lunar reconnaissance survey. Now the Soviet Union, the United States of America
and China have successfully implemented lunar orbiting exploration.