Chang'e 1 (; ) was an
uncrewed Chinese
lunar-orbiting
spacecraft
A spacecraft is a vehicle that is designed spaceflight, to fly and operate in outer space. Spacecraft are used for a variety of purposes, including Telecommunications, communications, Earth observation satellite, Earth observation, Weather s ...
, part of the first phase of the
Chinese Lunar Exploration Program. The spacecraft was named after the Chinese Moon goddess,
Chang'e.
Chang'e 1 was launched on 24 October 2007 at 10:05:04
UTC from
Xichang Satellite Launch Center. It left
lunar transfer orbit on 31 October and entered
lunar orbit on 5 November.
The first picture of the Moon was relayed on 26 November 2007. On 12 November 2008, a map of the entire lunar surface was released, produced from data collected by Chang'e 1 between November 2007 and July 2008.
The mission was scheduled to continue for a year, but was later extended and the spacecraft operated until 1 March 2009, when it was taken out of orbit. It impacted the surface of the Moon at 08:13 UTC.
Data gathered by Chang'e 1 was used to create an accurate and high resolution 3-D map of the lunar surface.
["China's map leaps over the moon"](_blank)
''Asia Times'' Chang'e 1 was the first lunar probe to conduct passive, multi-channel, microwave remote sensing of the Moon by using a microwave radiometer.
Its sister orbital probe
Chang'e 2 was launched on 1 October 2010.
Overview
The
Chinese Lunar Exploration Program is designed to be conducted in four
[Chang'e 4 press conference]
CNSA, broadcast on 14 January 2019. phases of incremental technological advancement: The first is simply reaching lunar orbit, a task completed by Chang'e 1 in 2007 and
Chang'e 2 in 2010. The second is landing and roving on the Moon, as
Chang'e 3 did in 2013 and
Chang'e 4 did in 2019. The third is collecting lunar samples from the near-side and sending them to Earth, a task for the
Chang'e 5 and
Chang'e 6 missions. The fourth phase consists of development of a robotic research station near the Moon's south pole.
[China's Planning for Deep Space Exploration and Lunar Exploration before 2030](_blank)
(PDF) XU Lin, ZOU Yongliao, JIA Yingzhuo. ''Space Sci''., 2018, 38(5): 591-592. The program aims to facilitate a crewed lunar landing in the 2030s and to possibly build an outpost near the south pole.
Objectives
The Chang'e 1 mission had four major goals:
# Obtaining three-dimensional images of the landforms and geological structures of the
lunar surface, so as to provide a reference for planned future soft landings. The orbit of Chang'e 1 around the Moon was designed to provide complete coverage, including areas near the north and south poles not covered by previous missions.
# Analysing and mapping the abundance and distribution of various chemical elements on the lunar surface as part of an evaluation of potentially useful resources on the Moon. China hopes to extend the number of elements studied to 14 (
potassium
Potassium is a chemical element; it has Symbol (chemistry), symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to ...
(K),
thorium (Th),
uranium
Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...
(U),
oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...
(O),
silicon (Si),
magnesium
Magnesium is a chemical element; it has Symbol (chemistry), symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 ...
(Mg),
aluminium
Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has ...
(Al),
calcium (Ca),
tellurium (Te),
titanium (Ti),
sodium
Sodium is a chemical element; it has Symbol (chemistry), symbol Na (from Neo-Latin ) and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 element, group 1 of the peri ...
(Na),
manganese
Manganese is a chemical element; it has Symbol (chemistry), symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese was first isolated in the 1770s. It is a transition m ...
(Mn),
chromium (Cr), and
lanthanum (La)),
[ compared with the 10 elements (K, U, Th, Fe (]iron
Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...
), Ti, O, Si, Al, Mg, and Ca) previously probed by NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...
's Lunar Prospector.
# Probing the features of the lunar soil and assessing its depth, as well as the amount of helium-3 (³He) present.[
# Probing the space environment between 40,000 km. (24854.8 mi) and 400,000 km (248548.5 mi) from the Earth, recording data on the solar wind and studying the impact of solar activity on the Earth and the Moon.
In addition, the lunar probe engineering system, composed of five major systems – the satellite system, the launch vehicle system, the launch site system, the monitoring and control system and the ground application system – accomplished five goals:
* Researching, developing and launching China's first lunar probe
* Mastering the basic technology of placing satellites in lunar orbit
* Conducting China's first scientific exploration of the Moon
* Initially forming a lunar probe space engineering system
* Accumulating experience for the later phases of China's lunar exploration program
]
Mission
According to the schedule, detailed design of the first program milestone was completed by September 2004. Research and development of a prototype probe and relevant testing of the probe were finished before the end of 2005. Design, manufacture, general assembly, test and ground experiments of the lunar orbiter were finished before December 2006.
Originally scheduled for April 2007, the launch was postponed until October as this was "a better time for sending a satellite into the Moon's orbit". Chang'e 1 was launched by a Long March 3A rocket at 10:05 GMT on October 24, 2007, from Xichang Satellite Launch Center in Sichuan
Sichuan is a province in Southwestern China, occupying the Sichuan Basin and Tibetan Plateau—between the Jinsha River to the west, the Daba Mountains to the north, and the Yunnan–Guizhou Plateau to the south. Its capital city is Cheng ...
Province.
After liftoff, Chang'e 1 made three orbits around the Earth, a burn at perigee extending the orbit's apogee further each time, until a final translunar injection burn placed it on course for the Moon on October 31, 2007. Another burn placed it in a polar orbit around the Moon, with burns at the periselenium of the first three orbits decreasing the aposelenium until it entered a final circular orbit. Lunar orbit insertion was achieved on the November 5, 2007. To mark this occasion, the probe transmitted 30 classical Chinese songs and musical pieces, including "My Motherland", "The Song of the Yangtze River", and "High Mountains and Flowing Water".
The probe was remotely controlled from stations at Qingdao and Kashgar, as the first use of the Chinese Deep Space Network. The ESA Maspalomas Tracking Station was also used to transmit signals to and from the probe.
The first pictures of the Moon were relayed on November 26, 2007. The probe was designed to orbit the Moon for one year, but operations were later extended, and it remained in lunar orbit until March 1, 2009.
End of mission
On 1 March 2009, at 08:13:10 UTC, Chang'e 1 crashed onto the surface of the Moon, ending its mission. According to the State Administration of Science, Technology and Industry for National Defense (China), this was a planned and controlled impact. Impact point was . During its orbital mission the probe transmitted 1,400 gigabits or 175 gigabytes (GB) of data.
Design and instrumentation
The Chang'e 1 spacecraft had a mass of , with a payload, carrying 24 instruments including a charge-coupled device
A charge-coupled device (CCD) is an integrated circuit containing an array of linked, or coupled, capacitors. Under the control of an external circuit, each capacitor can transfer its electric charge to a neighboring capacitor. CCD sensors are a ...
(CCD) stereo camera, microprobe instruments, and a high-energy solar particle detector.
* Stereo camera with an optical resolution of and spectrometer imager operating at wavelength
In physics and mathematics, wavelength or spatial period of a wave or periodic function is the distance over which the wave's shape repeats.
In other words, it is the distance between consecutive corresponding points of the same ''phase (waves ...
s of
* Laser altimeter with , laser, a range resolution of and a spot size of
* Imaging spectrometer
* Gamma and X-ray spectrometer working in an energy range of 0.5 to 50 keV for X-rays
An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ran ...
and 300 keV to 9 MeV for gamma ray
A gamma ray, also known as gamma radiation (symbol ), is a penetrating form of electromagnetic radiation arising from high energy interactions like the radioactive decay of atomic nuclei or astronomical events like solar flares. It consists o ...
s
* Microwave radiometer
A microwave radiometer (MWR) is a radiometer that measures energy emitted at one millimeter-to-metre wavelengths (frequencies of 0.3–300 GHz) known as microwaves. Microwave radiometers are very sensitive receivers designed to measure thermally ...
detecting 3, 7.8, 19.35 and 37 GHz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or Cycle per second, cycle) per second. The hertz is an SI derived unit whose formal expression in ter ...
with a maximal penetration depth of 30, 20, 10, 1 m (98.4, 65.6, 32.8, 3.3 ft) and a thermal resolution of 0.5 K
* High energy particle detector and two solar wind
The solar wind is a stream of charged particles released from the Sun's outermost atmospheric layer, the Stellar corona, corona. This Plasma (physics), plasma mostly consists of electrons, protons and alpha particles with kinetic energy betwee ...
detectors capable of the detection of electron
The electron (, or in nuclear reactions) is a subatomic particle with a negative one elementary charge, elementary electric charge. It is a fundamental particle that comprises the ordinary matter that makes up the universe, along with up qua ...
s and heavy ions up to 730 MeV
Achievements
* Chang'e 1 created an accurate and high resolution 3-D map ever of the lunar surface.
* Chang'e 1 conducted world's first passive, multi-channel, microwave remote sensing of the Moon.
See also
* Chinese space program
The space program of the People's Republic of China is about the activities in outer space conducted and directed by the China, People's Republic of China. The roots of the Chinese space program trace back to the 1950s, when, with the help ...
** Chinese Lunar Exploration Program (CLEP)
* Exploration of the Moon
* List of missions to the Moon
* List of artificial objects on the Moon
This is a partial list of artificial materials left on the Moon, many during the missions of the Apollo program. The table below does not include lesser Apollo mission artificial objects, such as a hammer and other tools, Laser Ranging Retroflect ...
References
External links
CLEP Official site
Chang'e 1 Mission Profile
b
NASA's Solar System Exploration
{{Orbital launches in 2007
Chinese Lunar Exploration Program
Missions to the Moon
Chinese space probes
Space probes launched in 2007
2007 in China
Spacecraft that impacted the Moon
2009 on the Moon
Spacecraft launched by Long March rockets