By: John Dotson
On January 3rd, PRC officials announced a successful landing by the Chang’E-4 probe (嫦娥四号探测器) in the Van Karman Crater near the lunar south pole. [1]The mission was noteworthy for being the first time that any lunar probe had successfully landed on the far side (or “dark side”) of the moon’s surface. [2] Chinese state media hailed the landing as both a scientific milestone and a “great achievement for the motherland” (Xinhua, January 4). NASA Administrator Jim Bridenstine joined other international voices in praising this latest achievement for the PRC space program, stating: “Congratulations to China’s Chang’e-4 team for what appears to be a successful landing on the far side of the Moon. This is a first for humanity and an impressive accomplishment!” (Twitter, January 2)
The Chang’E-4 probe and its associated Yutu-2 rover vehicle (玉兔二号巡视器) contain instruments for analyzing lunar geology, to include “a panoramic camera, infrared imaging spectrometer, and radar measurement devices, to obtain images of the moon’s surface and detect lunar soil and structure” (Xinhua, January 4). The probe also reportedly holds an experimental package of plant seeds and silkworm eggs, intended to monitor the ability of these organisms to survive and grow in the lunar environment. It further contains at least two sensor packages managed jointly with European partners: a particle detector from German researchers, and an ion detector from scientists in Sweden (National Geographic, January 2).
The History of China’s Lunar Exploration Program
The PRC’s Chang’E lunar exploration program, named for a goddess of the moon from Chinese mythology, dates back to the launch of the initial Chang’E probe in 2007. This first platform orbited approximately 200 kilometers from the moon over a period of 16 months, mapping the lunar surface and taking remote measurements of lunar soil, before ending in a controlled crash on the moon’s surface in March 2009. The second Chang’E mission, launched in October 2010, conducted similar surveys in lunar orbit before proceeding into deeper space, where it conducted a close fly-by of the asteroid “4179 Toutatis” in December 2012. Chang’E-3 was the first of China’s probes to actually touch down on the moon’s surface, landing in December 2013 in the Sinus Iridum Crater. Chang’E-3 and its associated Yutu-1 rover conducted geological surveys and astronomical observations until the two platforms experienced a series of technical difficulties, which resulted in a final loss of contact in July 2016 (Spaceflight Now, August 4 2016; Xinhua Backgrounder, December 8 2018).
Even as the Chang’E-3 mission was ongoing, PRC officials had indicated as early as May 2015 that the next planned mission, Chang’E-4, would be directed towards a landing on the far side of the lunar surface (Chinese Academy of Sciences, May 21 2015). It is likely that Chinese scientists were interested in the prospects for making genuinely new scientific discoveries amid the geological formations and astronomical vantage points of the moon’s unexplored far side; it is also likely that the opportunity to achieve a space exploration milestone held great patriotic appeal for PRC scientists and government officials alike. The successful deployment on January 3rd of both the lunar landing vehicle and its lunar rover provided a dramatic vindication of the aspirations announced nearly four years earlier.
The Planned Future of Chinese Lunar Exploration
Chinese exploration of the moon is unlikely to end with the current mission, and ambitious plans have already been announced for the future of the Chang’E program. A planned launch of the Chang’E-5 platform was originally scheduled for November 2017, but was scrubbed due to problems with the Long March 5 heavy launch rocket. Plans have since been announced for a Chang’E-5 launch sometime in 2019 (GB Times, April 25 2018).
Chang’E-5 is intended to be a lunar sample return mission, consisting of four modules: two will land in the Oceanus Procellarum (a lunar mare in the western region of the moon’s visible side), with one platform collecting geologic samples, and the second returning them to orbit; a third module will act as a docking station in orbit; and a fourth module in orbit will then return the samples to Earth (NASA Goddard Space Flight Center, December 7 2018). This multi-stage effort would be the most complicated yet attempted in the Chinese lunar program, and reflects a growing willingness by PRC space engineers to attempt increasingly challenging and complex operations.
In the wake of the successful Chang’E-4 landing, officials from the China National Space Administration made further announcements regarding future moon missions: a Chang’E-6 mission intended to bring back geologic samples from the lunar south pole; a Chang’E-7 mission to perform terrain and environment surveys in the same region; and aChang’E-8 mission to test technologies associated with a possible lunar research base (Xinhua, January 14). No projected dates have yet been announced for these missions.
The possibilities for such missions beyond Chang’E-5 point to ambitious plans on the table for the coming decades. In a promotional video jointly produced by the National Defense Technology Industry Agency (国家国防科技工业局) and the National Aerospace Agency (国家航天局) for the PRC’s “National Space Day” in April 2018, plans were announced to work towards a future manned outpost near the lunar south pole (China News, April 24 2018). Senior scientists involved with China’s lunar exploration program have suggested that such a lunar base might follow from manned missions to the moon, projected for the 2030s (GB Times, March 12 2018). These future Chinese efforts could involve Russian cooperation: Russian media announced in June 2018 that the two countries had agreed to establish a joint information center to support future lunar and deep space explorations (Moscow Times, June 8 2018).
The Queqiao Satellite and a Banner Year for China’s Satellite Industry
To support the Chang’E-4 mission, the Queqiao (“Magpie Bridge”) satellite (鹊桥卫星) was launched on May 21 2018, and entered its orbital position on June 14, 2018 (Xinhua, June 14 2018). The satellite now reportedly holds a halo-shaped orbital pattern in space around Lagrange Point 2, at a distance of approximately 455,000km from Earth (Xinhua, December 8 2018). [3] From this position, Queqiao acts as a signal relay for transmissions between the Chang’E-4 craft (and its rover) and mission control personnel on Earth (see image below). In addition, Queqiao is also equipped with another joint Sino-European project: the Netherlands-China Low-Frequency Explorer (NCLE), an experimental low-frequency radio astronomy device (Netherlands Institute for Radio Astronomy, undated).
A still image from a video produced by the China Academy of Space Technology that illustrates how the Queqiao satellite (lower right), orbiting around Lagrange Point 2 beyond the moon, acts as a signal relay for another platform in lunar orbit.(GB Times, December 19 2018).
The successful deployment of the Queqiao satellite received far less media attention than the Chang’E-4 lunar landing, but it demonstrates a development with potentially greater implications for China’s technological, commercial, and military future: namely, the PRC’s continuing successes in deploying an ever-more advanced array of orbital satellite systems. 2018 was a banner year for PRC space launches, with a combined 36 launches from the PRC’s two major launch centers in Jiuquan, Inner Mongolia and Xichang, Sichuan Province (MIT Technology Review, December 19 2018; NASA Spaceflight, December 21 2018).
Aside from the Queqiao operation, other successful satellite launches in 2018 included:
Eight pairs of satellites (sixteen total) for the Mark 3 Beidou (北斗) Satellite Navigation System were successfully sent into orbit in 2018, with official statements predicting the successful completion of the Beidou-3 constellation in 2020 (GB Times, November 19 2018; China Satellite Navigation Office, December 27 2018).
In early June, China launched what was reportedly the last of its Fengyun-2 (风云二号) series of meteorology satellites, which was hailed in state media as a means for China to assist countries participating in the Belt and Road Initiative with information regarding storms and other natural disasters (Xinhua, June 5 2018).
On December 21, the PRC sent into orbit the first in its series of Hongyun (虹云) satellites. When complete, the Hongyun constellation is intended to be a “network of 156 communications satellites into low Earth orbit… capable of covering every corner on the Earth, including the Arctic and Antarctica” (NASA Spaceflight, December 21 2018).
Implications for the Future
The landing of Chang’E-4 and its rover on the moon’s far side, and the successful deployment of the Queqiao satellite as a signal relay platform, both represent capstone achievements for China’s evolving space program. The PRC’s aspirations for space exploration are bold—particularly its declared goals of sending manned missions to the moon, and even constructing a habitable lunar base—and it remains to be seen whether practical engineering will successfully match soaring ambition. There is every indication, however, that the PRC is seriously applying attention and resources towards the achievement of these goals, which are bound together with national pride and the government’s intent to project an image of China emerging as a successful great power under the leadership of the CCP.
Beyond matters of national prestige, the PRC’s lunar exploration program—and in particular, the Queqiao satellite—also demonstrate how the continuing advancements of China’s space industry carry implications much closer to home. Queqiao demonstrates not only the advancing capabilities of the PRC space industry to support more challenging space exploration missions; it also displays the increasingly robust capacity of the PRC to place into orbit an ever-expanding array of satellites with broad commercial and military applications. Queqiao was perhaps the most dramatic Chinese satellite project of 2018, but it was accompanied by the successful deployment of dozens of other satellites that are steadily increasing the PRC’s capabilities (and potentially, competitive positions) in navigation, telecommunications, meteorology, and other fields. Even as inspiring images return from the far side of the moon, government, commercial, and scientific leaders should remain cognizant of the potential implications that PRC aerospace advancements may hold for the nearer-term terrestrial future.
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