How will Chang’e-7 achieve its objectives?
Chang’e-7 has 18 science payloads across its four spacecraft, including some built with international cooperation. The orbiter is equipped with five main scientific payloads, including a high-resolution stereo-mapping camera, a miniature synthetic-aperture radar, a wide-band infrared-spectrum mineral-imaging analyzer, a neutron-gamma spectrometer, and a magnetometer. It also features a hyperspectral imager from the Egyptian Space Agency and the Bahrain National Space Science Agency, a Moon-based Dual-channel Earth Radiation Spectrometer with involvement from Switzerland, and a space weather detector from the National Astronomical Research Institute of Thailand.
The lander carries a lunar seismograph to detect moonquakes, a lunar surface environment detection system, a landing camera, and a topography camera. It also carries a laser corner reflector from Italy, a dust and electric field sensor developed by the Space Research Institute of the Russian Academy of Sciences, and a wide-field telescope developed by the International Lunar Observatory Association in Hawaii.
The rover is equipped with a panoramic camera, a magnetometer, a Raman spectrometer, a lunar-penetrating radar, and an in-situ volatiles measurement system. The mission also includes a hopper, sometimes described as a mini-flying probe with legs, that carries a water-molecule analyzer. Queqiao-2 carries a further three payloads.
Following the light, flights into darkness
The rover is based on the Yutu rovers from the Chang’e-3 and Chang’e-4 missions of the 2010s and will analyze the surface and seek out subsurface water using a lunar penetrating radar. At the lunar south pole, where the Sun stays low on the horizon, spacecraft must effectively ‘follow the light’ to maintain power, avoiding long periods of darkness. After landing, the rover will begin taking images of itself, its companion spacecraft, and its surroundings. This data will be used to evaluate lighting conditions and plan drive routes and hibernation times to keep it illuminated by the Sun.
The hopper is designed for multiple flights, each of at least 10 kilometers (6.2 miles), targeting landings in dark, cold, shadowed craters. After landing in a shadowed crater, the hopper will move away from the area affected by its landing using its legs, then use its water molecule analyzer to drill for and extract material, aiming to detect water ice, methane, and other volatiles via mass spectrometry. The hopper will then need to return to sunlight to continue operating.
The hopper could become the second spacecraft, after NASA’s Ingenuity Mars helicopter, to make separate flights across an extraterrestrial body, but also be the first mobile legged spacecraft to carry out exploration beyond the Earth. Its findings could help confirm the presence of water ice on the Moon and mark a key step toward a potential sustained human lunar presence.
More resources
Scientific objectives and payload configuration of the Chang’E-7 mission
Selection of Landing Sites for the Chang’E-7 Mission Using Multi-Source Remote Sensing Data