According to the plan, Chang'e 1 has four mission goals to accomplish.
The first is to obtain 3-D images of the lunar surface in order to precisely ascertain the basic structures and physiognomy of the lunar surface and to initially map the lunar geology and structural elements to provide information for the follow-on soft landing.
The second goal is to analyze 14 chemical elements and their distribution across the lunar surface as well as outline distribution maps of the elements.
Third, it will measure the depth of the lunar soil.
Finally, it will explore the space environment between the Earth and the moon, collect original data of solar wind activity and study the solar impact on the space environment between the Earth and the moon. No nation has achieved any of the first three goals until now. For the last mission, it will be the first time for China to obtain data of space environment from the geostationary orbit.
The Payloads in Chang'e 1
To finish these four missions, Chang'e 1 carries six kinds of payloads, including a total of 25 devices arranged in eight instruments.
-- Optical Imaging System
- CCD Stereo Camera
- Interferometer Spectrometer Imager
-- Laser Altimeter
-- Gamma-/X-Ray Spectrometers
-- Microwave Detector
-- Space Environment Monitor System
- High-Energy Solar Particle Detector
- Low-Energy Ion Detector
-- Payload Data Management System
Among these instruments, the CCD optical system will use a series of three 2-D original images of a target area, taken before, during and after flyover, to reconfigure a 3-D image of the lunar surface. This demands higher accuracy in latitude control and orbital determination.
The Interferometer Spectrometer Imager is a camera that obtains images based on the fact that different objects have different spectrum properties. It will be used to perform multi-spectral remote sensing of the lunar surface. By filling spectral information into the digital lunar terrains obtained through stereo imaging, scientists will be able to conduct research on the properties of regional lunar resources and materials.
The Laser Altimeter will be used to provide complementary data to the elevation data of lunar surface and to refine the lunar surface digital model.
The Gamma-/X-ray spectrometers can collect information on the distribution of different elements according to the differences of energy spectra of gamma- and X-rays emitted by various elements due to cosmic ray excitation.
Microwave Detector: The microwave/millimeter-wave radiometer is usually used on satellite. According to the different depths penetrating into lunar soil of microwaves in different bands, lunar soil depth data can be obtained by measuring the microwave radiation brightness of the lunar surface material in given bands. This is a kind of passive measurement. The microwave detector on Chang'e-1 will operate in four different frequency bands.
Space Environment Monitor System: This is mainly used to measure the contents of heavy ions, energy spectra of protons and contents and spatial distribution of low-energy ions in solar wind.