“China’s small commercial satellite ‘Beijing-3’ may be one of the most powerful Earth observation satellites ever built, taking an image of downtown San Francisco (3,800 square kilometers) in just 42 seconds from a 500-kilometer orbit,” according to Chinese media quoting an SCMP report on December 28.
The Beijing-3 small commercial satellite was launched in June and was tested during a deep scan of the core of the San Francisco Bay Area, about 3,800 square kilometers, according to the report. The images were taken from a 500-kilometer orbit with a resolution of 50 centimeters per pixel. “The image is clear enough to identify a military vehicle on the street and determine what type of weapon it might be carrying.”
In a paper published in the journal Spacecraft Engineering, the research team led by Yang Fang, general project manager of Dongfanghong Satellite Co. said China started quite late in agile satellite technology, but has made many major breakthroughs in a short period of time. “They emphasize that this technology level has reached a world leader.”
Despite its small size and low cost, Beijing-3 is the most flexible satellite and probably one of the most powerful Earth observation satellites ever built, Sputnik said in a report cited on Dec. 28. In particular, it is two to three times faster than WorldView-4, one of the world’s most advanced observation satellites developed by the United States using similar technology, and has a 77 percent wider scanning band, but weighs only half as much.
In addition, the report said, most Earth-observing satellites normally must remain stable while taking images, otherwise they produce vibrations that blur the images. And satellites in lower orbits can only observe a narrow region below, so they must orbit the Earth several times or work with other satellites to cover the “region of interest.”
Beijing-3, however, rotates at 10 degrees per second to capture these high-precision photos of San Francisco, a mode that allows it to change the view of the ground from the on-board camera, thereby capturing a wider range of ground information.
In addition, the Beijing-3 satellite uses artificial intelligence technology to plan its own flight path, allowing it to make nearly 100 round trips in a day to monitor up to 500 areas of interest around the world. In addition, it can detect the presence of certain targets and send relevant photos back to the ground command center.
According to public reports, the Beijing-3 satellite was successfully launched on June 11 at the Taiyuan Satellite Launch Center on board a Long March 2D carrier rocket. It is a new high-performance optical remote sensing satellite, using a large number of innovative technologies, which will effectively improve China’s high-resolution remote sensing satellite data supply capacity.
According to the introduction, the Beijing-3 satellite is loaded with panchromatic and multispectral dual cameras, which can acquire panchromatic 0.5m and multispectral 2m resolution satellite images, achieving ultra-agile, ultra-stable and ultra-precise observation capabilities. It also adopts the technologies of intelligent mission planning, intelligent image processing and intelligent composite control. These innovative technologies make Beijing-3 not only have powerful image acquisition capability, but also can provide unique imaging modes.
“For example, it can actively push and sweep images along rivers, highways and other arbitrary trajectories,” said Yang Fang, head of the Beijing-3 satellite model, in an interview. This transit can obtain high-definition images of the entire Yangtze River basin, and can also carry out rapid multi-angle imaging to obtain three-dimensional information of features in all directions.