China begins construction of ultra-low orbit satellite constellation

The China Aerospace Science and Industry Corporation Limited (CASIC) has announced the official start to the construction of an ultra-low orbit satellite constellation.

The CASIC made the announcement at the opening of the 9th China (International) Commercial Aerospace Forum, which kicked off on Wednesday in Wuhan, central China's Hubei Province.

The CASIC said the first satellite of the ultra-low orbit satellite constellation will be launched in December, carrying payloads such as an optical remote sensing camera, spaceborne intelligent processing equipment and an atomic oxygen detector.

An ultra-low orbit is an orbital altitude of less than 300 kilometers. Its dynamic environment is complex and needs to offset the effects of the rapid decay of the satellite orbit due to heightened atmospheric drag.

Despite technical challenges with long-term operations, ultra-low orbits have high value. With lower orbit altitudes, Earth observation can shift from remote sensing to near observation, which has lower costs, higher resolution and shorter transmission delays.

The ultra-low orbit satellite constellation will achieve 0.5-meter spatial resolution and transmit spatial information to users within 15 minutes, according to Zhang Nan, the chief designer of the constellation.

The satellite constellation can provide effective data support for emergency rescue, fire monitoring, and disaster prevention and alleviation work.

The CASIC plans to complete the launch of a nine-satellite cluster in 2024, and complete a network of 192 satellites in orbit by 2027.

By 2030, 300 satellites are expected to be operating in orbit, providing diversified and real-time remote sensing services, and realizing global 15-minute response capabilities.