China has stayed busy over the last week, launching a new set of Tianhui-6 satellites into space while detailing plans for their first lunar missions in 2030. Furthermore, a new change could impact the Chang Zheng 5B rocket and reduce the chances of an uncontrolled reentry. Finally, an EVA was conducted on the Tiangong Space Station, with China altering communication strategies during the EVA.
Launch of Tianhui-6 A/B
China launched the Tianhui-6 A/B mission from the Taiyuan Satellite Launch Center (TSLC) onboard a Chang Zheng 4C rocket on Thursday, March 9 at 22:41 UTC. The Tianhui-6 twin satellites will be used for geographic mapping, land resource surveys, scientific experiments, and more.
Tianhui translates to “sky-drawing” and is a series of unclassified cartography satellites operated by the China Aerospace Science and Technology Corporation (CAST). With the mission patch featuring a dolphin, there is some speculation that the satellites might be related to ocean surveillance and mapping. CAST DFHSat, a subordinate company of CAST, is listed as the manufacturer of the satellites.
The two satellites launched to an 888×880 km orbit with an inclination of 99 degrees. It was confirmed later that the exact liftoff time was 22:41 UTC.
The Chang Zheng 4C (Long March 4C) rocket was used for this mission. The CZ-4C features three stages and can loft 4,200 kg into a low Earth orbit (LEO) and 2,800 kg into a Sun-synchronous orbit (SSO). Its first-stage engine is the YF-21C, the same engine used on the Chang Zheng 2, Chang Zheng 3, and Chang Zheng 4 vehicles.
China Reveals Moon Lander
As part of a space exhibition in the National Museum of China, China has revealed their next generation lunar lander, which is expected to carry the first Chinese astronauts to the lunar surface around 2030.
The spacecraft will land on the surface with the help of a propulsion stage, which will reduce most of the lander’s velocity before landing, which the lander itself will perform using engines integrated into the lander. The lander is currently designed to take two astronauts to the lunar surface.
Initially, the length of these Chinese lunar missions will only be hours to demonstrate the technologies of the mission. Later missions are expected to be longer in duration, eventually leading to long-term missions on the surface.
At the conclusion of the mission’s surface activities, the lunar lander will carry the astronauts back into space. A newly designed spacecraft will be waiting for the crew in orbit, eventually taking them back to Earth. This spacecraft has already seen significant hardware testing, with a prototype launching on a Chang Zheng 7 rocket in 2016 and a second test flight of the “next-generation crewed spacecraft test vehicle” and the “flexible inflatable cargo re-entry capsule test capsule” on a Chang Zheng 5B in 2020. Both tests have seemingly been successful, proving the technology for potential moon missions in the future.
What’s more, the Chinese lunar program includes the potential for a Chinese lunar space station and other robotic Lunar exploration missions.
Upcoming Super-Heavy Rocket Finally Named
Previously only referred to as the “921 rocket,” “next Generation crewed launch vehicle,” or “Chang Zheng 5 variant,” China’s upcoming super-heavy lift rocket, which is set to take the country’s first astronauts to the Moon, has finally received its name.
The super heavy-lift launch vehicle, featuring three Chang Zheng 5 center cores, will be named Chang Zheng 10. It is a 5-meter diameter rocket powered by seven YF-100K engines on each core, bringing the thrust of all three cores to 26.25 mN at liftoff. CZ-10 will stand around 90 meters in height and will have a mass of 2,187 metric tonnes. Overall, the rocket will feature three stages, with the second stage being powered by two vacuum-optimized YF-100M engines and the third stage featuring three YF-75E hydrogen engines.
At the 2022 Zhuhai Airshow, a model of CZ-10 was displayed, showing the current design of the rocket. The rocket’s primary goal is to enable China to loft 25 tonnes of payload to the Moon with each launch. Chang Zheng 10’s debut flight is currently slated for sometime in 2027.
After Chang Zheng 10, China plans to build an even bigger rocket with a reusable first stage called Chang Zheng 9. Dr. Long Lehao, the head designer of the rocket, recently briefed the public on the vehicle’s design and progress. The updated design sees yet another engine switch, which comes after multiple previous methane and RP-1 engine swaps. As of now, the rocket features 30 200-ton methalox engines on its first stage.
Overall, the rocket stands 114m tall in its current design, with a diameter of 10.6 meters. The China Academy of Launch Vehicle Technology (CALT) recently unveiled its first 10-meter diameter propellant tank, paving the way for the technology and construction techniques needed for the development of CZ-9.
While China’s initial efforts to get to the Moon will mostly utilize CZ-10, the CZ-9 might come in later to reduce the cost of missions to the Moon and to enable the launching of heavier payloads to the Moon, such as a planned lunar station. CZ-9 is not expected to debut before the 2030s.
Chinese Commercial Launch License Amended
In a change to the regulation of commercial launch licenses, the National Defense Administration of China updated its requirements regarding the deorbiting of rocket stages. In the new regulation, a Chinese commercial launch vehicle would have to deorbit the last sub-stage of a launch vehicle after passivation and other measures. This could influence future launches of the Chang Zheng 5B rocket, which has seen significant pushback from international partners, as its sustainer stage remains in a very low LEO after separation, leading to its uncontrolled reentry days later.
👀 Chinese State Admin. of Sci. Tech. & Ind. for National Defense, supervising CNSA, published amendments of regulation of commercial launch licenses including one that requires deorbiting upper stages. Great news if that means the next Long March 5B core stage will be suborbital https://t.co/shovtN5XVZ pic.twitter.com/4dYYtDeraL
— China 'N Asia Spaceflight 🚀🛰️🙏 (@CNSpaceflight) March 8, 2023
CASC has previously confirmed that the Chang Zheng 5B would be upgraded with a Yuanzheng-2 boost stage to enable a launch in the 2nd half of 2023. This might be related to a Chinese internet constellation similar to SpaceX Starlink or Amazon’s Project Kuiper. It remains to be seen how China will handle the de-orbiting of the CZ-5B stage.
Chinese EVA Conducted on Tiangong Space Station
Aboard the Chinese Tiangong Space Station in LEO, the Shenzhou-15 crew recently conducted their second spacewalk. However, China did not provide detailed information about this spacewalk, including the spacewalk’s start time, end time, or length, leaving the purpose of the spacewalk a mystery. Currently, speculation suggests that the spacewalk was conducted around or on Feb. 28.
Taikonauts Fei Junlong and Zhang Lu were the two astronauts who conducted the spacewalk, while Deng Qingming supported the spacewalk with the help of the robotic arm from within the Tianhe Core Module.
The secrecy of this spacewalk is unusual when compared to previous spacewalks on Tiangong. Previously, China has released videos and detailed information about the spacewalks, such as the installed elements and duration of the spacewalk. It is unclear why this practice was stopped for this event.
(Lead image: Liftoff of CZ-4C. Credit: CASC)