Chinese engineers achieve satellite rescue using gravity slingshot
Chinese engineers successfully rescued two satellites that had been on the wrong orbit for 123 days, using an innovative "gravitational slingshot" method. According to scientists, these satellites will enable the piloting and autonomous control of unmanned spacecraft.
On 15th March at 12:15 PM Greenwich Mean Time, China launched two satellites atop a Yuanzheng-1S upper stage, mounted on a Long March-2C rocket. Although the first and second stages were successful, a technical issue with the upper stage prevented the satellites from reaching their intended orbit. After several months of rescue attempts, Chinese engineers sought a solution that included deorbiting the satellites so they would burn up in the atmosphere.
Using the Earth's, Moon's, and Sun's Gravity
For 123 days, Chinese engineers worked to rescue the satellites, ultimately succeeding thanks to a gravitational manoeuvre. In brief, the engineers utilised gravity to direct the satellites onto the correct orbits. Their efforts saved the satellite mission and demonstrated a manoeuvre that could revolutionise deep space navigation.
The gravitational manoeuvre that saved the Chinese satellites involved using the gravitational force of the Earth, the Moon, and the Sun to direct the satellites onto the correct orbits. This allowed the engineers to regain control of the satellites, which were too close to Earth and spinning uncontrollably.
In an interview with CGTN Digital, Zhang Hao, a researcher at CSU, recalled that during his first mission, he initially did not focus on the launch problems. He noted that if the satellites had been destroyed, it would have meant the loss of years of work and investment. Zhang Hao explained that the team was divided into two groups: one remotely controlled the satellite engines to slow their rotation, while his team calculated the best route to bring the satellites back on course.
Future plans for the Chinese satellites
Satellites DRO-A and DRO-B have joined the previously launched satellite DRO-L, forming a constellation designed to provide navigation services for spacecraft. According to Mao Xinyuan, another researcher at CSU, these satellites will allow for the localisation of a spacecraft within three hours, marking significant progress compared to current methods. Mao stated that these satellites will allow for the piloting of unmanned spacecraft and enable autonomous control.
These satellites are part of China's plans to increase its presence around Earth and the Moon. The aforementioned autonomous piloting will be crucial for sending crewed missions to the Moon by 2030 and supporting the construction of the International Lunar Research Station (ILRS).
