A reusable uncrewed space vehicle returned to Earth on Monday morning after 276 days in orbit – more than 100 times longer than its maiden flight less than three years ago, Chinese space authorities said.
China Aerospace Science and Technology Corporation, the nation’s biggest space defense contractor, hailed the classified mission as a “complete success”, saying it “marks an important breakthrough” in China’s research into the technology.
Reusable spacecraft “will provide a more convenient and cost-effective way for peaceful use of space”, the company said.
Little is known about the craft – which spent two days in orbit on its first mission in September 2020 – and China’s space authorities have not released any pictures or technical data.
Some experts suspect the Chinese craft could be equipped with advanced imaging and sensing equipment to gather intelligence on potential targets or monitor sensitive areas of interest.
Another potential use is the deployment of small satellites or other payloads into orbit. This could include communications satellites, navigation systems, or other types of sensors that could be used for military or government purposes.
Based on the payload capacity of the Long March 2F rocket which launched the reusable spacecraft, experts say it is likely to be similar in size and design to the US Air Force’s Boeing X-37B.
The US craft last year spent a record 908 days in orbit on its fifth flight since it was introduced in 2010. At around 9 meters (29.5 feet) long and 3 meters high, the X-37B has a mass of around 5,000kg (11,000lbs) and is designed to fit inside the payload fairing of a standard rocket.
The US spacecraft has a distinctive shape, with a flattened wedgelike body and a wingspan of about 4.6 meters ending in angled wingtips to give it a slightly boomerang-like appearance. The wings are angled at about 45 degrees and swept back towards the tail of the spacecraft.
This compact and streamlined design allows the X-37B to operate efficiently in space while also fitting within the constraints of existing launch vehicles.
China and the United States have been in a race to develop smaller, unmanned reusable spacecraft since 2011 when the space shuttle program was discontinued for a range of reasons, including high costs and safety concerns.
Uncrewed spacecraft are cheaper and more efficient to design and operate, with no need for life support systems or other accommodation. Their size also means they can be launched by smaller rockets, which are generally less expensive than larger launch vehicles, like those used for the space shuttle.
A reusable spacecraft can be used multiple times, allowing for more efficient space travel at a lower cost. This differs from most spacecraft in use today, which are typically designed for one-time use and are discarded after completing their mission.
The push to develop the technology could have significant implications for the power struggle between the US and China. The spacecraft potentially provide a strategic advantage in areas such as military reconnaissance, satellite deployment and space-based weapons systems.
There are many challenges in reusable spacecraft development, including the need for advanced heat shielding to protect it during re-entry, as well as robust and reliable landing systems, and reliable and efficient propulsion systems.
Extended periods in orbit can add further complications, such as maintaining the spacecraft’s power supply, which requires advanced solar panels or other generation systems that can operate reliably in space.
The spacecraft’s thermal environment must be able to withstand extreme temperature fluctuations as it moves between sunlight and shadow. Long-term exposure to radiation can also damage the sensitive on-board electronic components.
Keeping the spacecraft in lower-Earth orbit for an extended period also requires precise control over its trajectory and orientation. These can be affected by atmospheric drag, gravitational forces from other celestial bodies and other factors – including solar winds.
Engineers must carefully design the spacecraft’s propulsion system to ensure that it can make the small adjustments to its trajectory needed to maintain a stable orbit, or to approach a target, depending on its mission. (SCMP)