China has had a bumper few years in space exploration and its ambitions are about to get bolder. China’s National Space Administration has released an outline of its plans for the next five years, which include launching a robotic craft on an asteroid, building a space telescope to rival Hubble and laying basics of a space-based gravitational wave detector.
The missions were highlighted in a white paper, “China’s Space Program: A 2021 Perspective,” released last month. The plans continue the country’s trend of emphasizing science-driven missions, rather than technology development and applications, said Shuang-Nan Zhang, an astronomer at the Institute of High Energy Physics in Beijing. “It’s a very good sign,” he said. “It’s a continuous increase in investment in the exploration of the Universe.”
Nature takes a look at five of the most ambitious projects.
Visit an asteroid
China aims to launch asteroid probes to sample near-Earth asteroids and study icy comets that have asteroid-like orbits. The mission, which will likely be named ZhengHe after a Ming Dynasty Chinese explorer, would be the country’s first to visit an asteroid and could be launched as early as 2024. It will follow in the wake of successful Japanese missions to the Hayabusa and OSIRIS asteroids. from NASA. -Rex, who is to send space rocks back to Earth next year.
ZhengHe will fly for ten years, first landing on an ancient asteroid known as HO3 or Kamo’oalewa, which loops around the Earth like a quasi-satellite (see Earth’s Pet Rock). Scientists hope his study will give them insight into conditions at the start of the solar system. ZhengHe will anchor on the asteroid before picking up its sample, according to a correspondence1 Posted in natural astronomy Last year. ZhengHe will return to Earth orbit in 2026 to deposit its loot, which will be parachuted to the ground. The craft will then launch slingshots around Earth and Mars and travel into deep space towards Comet 311P/PANSTARRS.
To a moon base
Not content with returning the first lunar samples to Earth since the 1970s, China approved three more lunar missions in December, all focused on the moon’s south pole, where the country plans to build a lunar base.
Chang’e-7, slated for launch in 2024, will carry out a detailed survey of the Moon’s south pole, including mapping the distribution of ice in its shadowed craters. Chang’e-6 will follow, aiming to bring back samples of polar soil. The ice is a treasure for scientists, who can use it to study the Moon’s history, and for prospectors, who hope to use it as rocket fuel and to power lunar bases.
Work will also begin on Chang’e-8, which is not scheduled to fly before 2030; this will test “basic technologies” for a crewed international lunar research station – the goal of China’s lunar program beyond 2025. Russia and China will sign an intergovernmental agreement on building a research base together “as soon as possible this year,” Wu Yanhua, deputy administrator of the China National Space Administration (CNSA), said at the white paper’s launch press conference. He stressed, however, that the venture was open to all nations.
Wu added that China is willing to broaden and deepen international collaboration, including on lunar exploration; on the Chinese space station, Tiangong, which is under construction; and on planetary exploration.
March and beyond
China made its first leap into interplanetary space with the Tianwen-1 orbiter, which dropped a lander containing the Zhurong rover on Mars in May. According to the white paper, China will complete its research to send a craft to Mars to sample rocks and bring them back to Earth. This mission could launch in 2028. (NASA’s Perseverance rover collected the first rocks from Mars in 2021. The agency hopes to bring them back to Earth in a joint mission with the European Space Agency (ESA) , launched in 2026.)
The white paper also outlines China’s plans to possibly probe deeper into the solar system. The next five years will see the completion of key research for a mission to explore Jupiter and its ocean-filled lunar system. News reports suggest this mission could be launched as early as 2029, meaning it would join ESA’s JUICE mission and NASA’s Europa Clipper mission, which are scheduled to fly in 2023 and 2024. , says Zhang.
The country also aims to explore the limits of the solar system. Chinese funding agencies have yet to confirm this, or the Jupiter mission, but “a mention in the plan is certainly helpful,” says Zhan Hu, an astronomer at the National Astronomical Observatories in Beijing.
A new Hubble: the Xuntian Space Telescope
China also plans to launch a space telescope called Xuntian, whose name means “to survey the skies.” This will produce images in the same wavelengths – ultraviolet, visible and infrared – as those used by NASA’s Hubble Space Telescope.
Slightly smaller than Hubble, Xuntian won’t quite match the resolution of its predecessor; but, at any time, Xuntian will capture a piece of sky 300 times larger. This will allow it to probe a much larger volume of the Universe than Hubble, says Zhan, who works on Xuntian.
Most of Xuntian’s first 10 years will be devoted to understanding the history and evolution of the Universe through extensive study of the sky. The telescope will periodically dock with China’s space station, Tiangong, for refueling and maintenance. Zhan says the team expects to deliver the telescope by the end of 2023, ready for launch in 2024. “The schedule is very tight,” he says.
Detect gravitational waves in space
China wants to further develop its plans to launch a space-based gravitational wave detector, called Taiji, in the early 2030s. If launched then, it would be the first of its kind. Such a mission would observe waves of lower frequency than those seen by ground-based detectors such as Advanced LIGO, allowing it to detect higher-mass black holes, including those in the early Universe.
But the experiment would be complex: spotting ripples in space-time would amount to detecting shifts of just a few trillionths of a meter in the distances between three spacecraft, positioned 3 million kilometers apart of triangle.
A first pilot satellite, called Taiji-1, successfully completed its mission in 2019, and researchers now hope to fly a two-satellite mission in 2024-25 to test the necessary precision technologies. This will “remove all technical obstacles” for Taiji’s ultimate mission, says Yue-Liang Wu, a physicist at the University of the Chinese Academy of Sciences in Beijing.
ESA has long planned its own gravitational wave observatory, LISA, and has already successfully piloted a pathfinder. But LISA is not expected to launch until 2037. Together, the two arrays could be used to measure the Hubble constant, which describes the expansion of the Universe, with far greater precision than ground-based detectors, the researchers say. at the origin of the mission.