"Chang'e-3" successfully soft-landed at 19.51°W, 44.12°N in the northern part of Mare Imbrium at 21:11 on December 14, 2013, becoming the first lunar probe of the former Soviet Union in 1976. The first probe to soft-land on the lunar surface since the 24th.
Immediately, Chang'e-3 carried out joint detection of lander placement detection and lunar rover lunar surface patrol survey, and began to carry out scientific detection such as "lunar exploration, sky survey, and earth observation": the lunar surface morphology and Geological structure survey, lunar surface material composition and available resources survey, earth plasma layer detection and lunar-based optical astronomical observation. According to the scheduled detection plan, Chang'e-3 has achieved a series of important results.
In order to commemorate China's first successful landing on the moon, the International Astronomical Union also officially named the 77-meter area around the Chang'e-3 landing site (blue box area in Figure 4) as "Guanghan Palace" ".
During the entire scientific exploration period, in addition to the images and terrain data obtained by the camera equipment, other payloads also obtained a large amount of scientific data:
Moon-based optical telescope : For the first time in the world, independent astronomical observations were carried out relying on an extraterrestrial celestial body platform.
The moon-based astronomical telescope gets rid of the limitations of the atmospheric window and achieves scientific detection of various types of celestial bodies (stars) in the near-ultraviolet band (detection band 245~340nm) on the lunar surface. It is the first time in the world Achieve independent astronomical observations based on extraterrestrial celestial body platforms.
The lunar-based optical telescope is also the equipment with the longest working time among all the scientific instruments of Chang'e-3. It is turned on for about 12 to 18 hours every day during the lunar day. As of June 2018, the lunar-based astronomical telescope The cumulative observation time is approximately 6,962 hours, and more than 340,000 image data have been acquired, providing research support for basic scientific topics such as stellar evolution, compact star and black hole physics, and high-energy celestial objects.
Extreme Ultraviolet Camera: For the first time, image data of the Earth's plasma layer obtained from moon-based large-angle observations were obtained.
The extreme ultraviolet camera on the lander can conduct large-angle, long-term observation and research on the 30.4nm radiation generated by the Earth’s plasma layer, and obtain image data of the Earth’s plasma layer. This is the first time in the world that it has been used on the lunar surface. An imaging instrument working in the extreme ultraviolet band.
As of June 12, 2014, the extreme ultraviolet camera has been conducting observations of the Earth's plasma layer during each day of the month. The *** acquired 1,045 image data, with a cumulative observation time of about 230 hours, providing detailed and credible data for studying the structure and dynamics of the plasma layer, as well as the electric field distribution.
Lunar radar: Obtain scientific data related to lunar soil thickness distribution and lunar subsurface geological structure.
The lunar radar mounted on the Chang'e-3 rover is a dual-channel antenna radar. Its first channel has a working center frequency of 60MHz, a thickness resolution of meter level, and a detection depth of greater than 100m; the second channel The working center frequency is 500MHz, the thickness resolution is less than 30cm, and the detection depth is greater than 30m.
As of April 27, 2014, the lunar radar has been powered on for 8.3 hours, and the effective detection distance is about 109 meters. It has acquired 18,513 channels of echo data from the first channel of the radar. The 32,381 channels of two-channel echo data provide basic data for the study of lunar soil thickness distribution and lunar subsurface geological structure.
Infrared imaging spectrometer: obtain spectral data.
The infrared imaging spectrometer mounted on the Chang'e-3 rover has detected the material types and mineral composition of the lunar surface in the patrol area. The cumulative working time is about 8.8 hours. As of the end of the second month, the normal working mission of the instrument has ended. *** conducted spectral detection on 4 lunar soil objects, and in total *** obtained 840 frames of visible near-infrared (spectral range 450nm ~ 950nm) spectral image data and 2240 frames of shortwave infrared (spectral range 900nm ~ 2400nm) spectral data. Provided data for the study of mineral composition near the landing site.
Particle excitation x-ray spectrometer: obtain energy spectrum data.
The particle-induced X-ray spectrometer (energy range 0.5-20keV) carried by Chang'e-3 lasted about 4 hours on the lunar surface and analyzed the chemical composition of lunar soil samples at two locations. In total, 2091 frames of energy spectrum data were obtained. It provides data for studies such as elemental composition inversion near the landing site.