Chang'e 7 to Start Searching for Lunar Water Ice in Mid-2026
Over a dozen Chinese and international instruments will operate on and around the Moon for almost a decade.
China is preparing to begin its latest and longest robotic lunar missions to date, with many global partners riding along.
Formally approved in September 2022, the Chang’e 7 lunar mission will orbit and land on the Moon in 2026. The approximately 8,200-kilogram spacecraft will be the latest evolution of the Chang’e mission stack, which started as a singular lander for Chang’e 3 and 4 before gaining an orbiter and ascent hardware for the Chang’e 5 and 6 sample return missions. With Chang’e 7 hardware for ascent into lunar orbit and returning samples to Earth has been removed to enable the delivery of other scientific and exploration hardware.
Like China’s last two missions to the Moon, Chang’e 7 will be launched atop of a Long March 5 launch vehicle from Launch Complex 101 at the Wenchang Space Launch Site. A launch date of August 2026 is currently being worked toward, according to experts involved with the lunar exploration program.
A few days after launch, Chang’e 7’s mission stack will enter a lunar orbit that overflies both of the Moon’s poles to study and examine potential landing sites at the south pole, selected for research into lunar water ice. Via a presentation at the United Nations Committee on the Peaceful Uses of Outer Space, it is known that the preferred site is a permanently illuminated peak next to Shackleton crater, at 123.4 degrees East and 88.8 degrees South, with backup sites nearby as well as other less preferred sites of interest near craters Shoemaker and Haworth, also constantly illuminated.
When Chang’e 7 will land at the south pole depends on lighting conditions across the desired sites, both for studying their condition and for the automated landing. Examination of the landing site is expected to take up to two months. Regardless of when, landing software onboard the lander will be an adjusted version of Chang'e 5/6’s, which itself is modified from Chang’e 3/4’s, allowing for suitable hazard avoidance and relocation to other sites during descent.
Science and global partners
Once in proximity to the Moon, and on the surface, a suite of over a dozen instruments will be active. Those instruments, according to China’s Lunar Exploration Program’s Chief Designer, Wu Weiren (吴伟仁), will:
“[Find] traces of ice at the south pole, investigate the environment and weather there, and survey its landforms. It will also be tasked with detecting the natural resources beneath the [lunar] south pole’s surface. Moreover, mission planners are considering if we can use the probe to dig into the surface to check the underground structures and compositions.”
As for the choice of the lunar south pole, that was for the near constant sunlight available as well as its stable temperatures, but on ice Wu added:
“[It] lies in water. The permanently shadowed craters on the south pole may harbor reservoirs of ice and other volatile compounds, and they will be valuable resources for manned explorations.”
With that in mind, the China National Space Administration’s goals for the Chang’e 7 mission are:
Investigation and study of lunar surface environment and water ice in its soil.
High-precision investigation and study of morphology, composition and structure of the Moon.
Investigation and study of interior structure, magnetic field and thermal characteristics of the Moon.
General investigation and study of surface environment of the south pole of the Moon.
Moon-based observation and study of the Earth’s magnetotail and plasmasphere.
To fulfill those goals, Chinese institutions have equipped the mission with fifteen instruments across its orbiter, lander, rover, and hopper.
The orbiter has five Chinese instruments onboard, where they will see much of the Moon during its orbit. Those instruments are:
High-Resolution Stereo Mapping Camera: taking detailed black and white photos of the lunar surface, with a 0.5-meter resolution from 100 kilometers altitude, and a 0.075-meter resolution from 15 kilometers altitude.
Miniature Synthetic Aperture Radar: using radar waves to image the surface through darkness and shadows with better than 1 meter resolution.
Wide-Band Infrared Spectrum Mineral Imaging Analyzer: which identifies and maps different minerals on the lunar surface using visible and infrared light.
Lunar Neutron Gamma Spectrometer: to detect neutrons and gamma rays to find water ice and map the distribution of different chemical elements.
Lunar Orbit Magnetometer: which measures the strength and direction of magnetic fields around the Moon.
Meanwhile, the lander has four instruments from China’s institutions, which are:
Landing Camera: to photograph the landing site during descent and after touchdown.
Topography Camera: to capture pictures of the surrounding terrain and landscape features.
Lunar Seismograph: for detecting moonquakes and seismic vibrations to study the Moon’s internal structure.
Lunar Surface Environment Detection System: for monitoring charged particles, radiation, electric and magnetic fields, and dust activity at the landing site.
After a soft touchdown at the south pole, the lander will deploy a rover (based on Yutu and Yutu-2), powered up by upright-standing solar panels. Five instruments are on the rover for its travels to nearby craters, those are:
Panoramic Camera: for capturing wide-angle images of the surrounding landscape as the rover moves.
Rover Magnetometer: to measure local magnetic fields on the surface with very high precision.
Lunar Raman Spectrometer: for identifying minerals in rocks and soil by analyzing how they scatter laser light, including via microscope imaging.
Lunar Penetrating Radar: for sending radar pulses into the ground to reveal subsurface layers and natural structures up to 400 meters deep.
In-Situ Measuring System of Volatiles on the Lunar Surface: to analyze gases and volatile compounds in the lunar soil, and detecting water, methane, ammonia, and other substances.
Chang’e 7 also has a smaller hopper that will head into permanently shadowed craters during short trips. The sole instrument onboard it is the Lunar Soil Water Molecule Analyzer, for, as the name suggests, measuring water in the lunar soil.
Alongside the Chinese instruments, six more are from global contributors, each weighing up to ten kilograms on the lander or fifteen kilograms on the orbiter. Unsurprisingly, Russia is providing a lunar dust and electric field probe (on the lander) to measure plasma in the lunar surface environment. Meanwhile, Egypt and Bahrain are jointly working on a hyperspectral camera (attached to the orbiter) to study lunar geology and the composition of resources on the surface. Thailand has worked on a hodoscope to detect high-energy particles (from the orbiter) and how they are influenced by the Sun, Earth, and Moon. Switzerland has contributed a spectrometer that will face toward Earth (from the orbiter) to measure radiation going to and from our planet, and Italy has made a laser retroreflector array (onboard the lander) for precisely measuring the distance to the Moon from Earth.
Somewhat surprisingly, a U.S. item will be onboard in the form of the International Lunar Observatory Association’s wide-field optical telescope, which will image the Milky Way and the Galactic Center (from the lander). A partnership with the University of Hong Kong’s Laboratory for Space Research has allowed for its inclusion on board the mission.
All of the international experiments have reportedly been delivered for integration and testing with Chang’e 7.
Into the 2030s
As of September 2023, the Chang’e 7 orbiter and lander are planned to be operational for eight years to allow for a wealth of scientific data from its instrument suite. That will have both spacecraft online until 2034, but with the year-long Chang’e 3 currently in its twelfth year and Chang’e 4 approaching year seven (with Yutu-2), there’s a good chance the mission lasts far longer.
Chang’e 7 is also part of the reconnaissance phase of the thirteen-nation-member China-led International Lunar Research Station, being the nation’s last mission before the implementation phase (starting with Chang’e 8). As part of that phase, its mission goals are important to further robotic and crewed exploration and scientific research into the Moon by an international cohort.