HELSINKI — China conducted a pair of launches last week to replenish its Beidou navigation system and send science and radar tech test satellites into orbit.

A Long March 2C rocket lifted off at 4 a.m. Eastern May 21 from the Jiuquan Satellite Launch Center in the Gobi Desert. Aboard were the Macau Science Satellite 1A and 1B, designed to study the Earth’s magnetic field, and the Luojia-2 (01), a Ka-band synthetic aperture radar (SAR) test satellite for Wuhan University.

Macau Science Satellite 1A carries payloads for measuring the Earth’s magnetic field while 1B features high-energy particle detectors and solar X-ray instruments. The pair will provide complementary observations to those made by ESA’s Swarm satellites and the Sino-Italian seismo-electromagnetic satellite, Zhangheng-1. The satellites will also monitor the South Atlantic Anomaly (SAA), a weak spot in Earth’s magnetic field which impacts the operations of spacecraft. 

The platform for satellite 1A was developed by DFH Satellite under the China Academy of Space Technology (CAST), the main satellite-making arm of China’s main space contractor, CASC, while 1B was developed by Northwestern Polytechnical University. The payloads were developed by the Macau University of Science and Technology (MUST).

Luojia-2 (01) is testing multi-angle and video radar imaging, with a highest resolution of 0.5 meters in spotlight imaging mode. It will also test signal enhancement and integration of remote sensing imaging, meteorological detection and water conservancy applications, according to Chinese media reports. It continues a surge in SAR developments in China.

The 353-kilogram Luojia-2 was developed by Wuhan University. The first satellite, Luojia-1, launched in June 2018 and had a mass of 20 kilograms.

The launch of the satellites was facilitated by the China Great Wall Industry Corp. (CGWIC), another CASC subsidiary, which is authorized to provide commercial launch services, as well as satellites and engage in international space cooperation.

Prior to this, a Long March 3B lifted off from Xichang Satellite Launch Center in southwest China at 10:49 p.m. Eastern, May 16. Aboard was the 56th satellite for China’s Beidou navigation and positioning system, and is headed for geostationary orbit. 

It is the first backup satellite for the Beidou system, which was completed in 2020. The new satellite is part of an overall aim to improve the system’s availability, stability, short message communication capacity and positioning precision.

The launches were China’s 19th and 20th of 2023 so far. CASC plans more than 60 launches this year, while commercial actors could add more than 20 orbital missions, according to announced plans. 

A Long March 2F rocket was rolled out at Jiuquan May 22 ahead of launch of the Shenzhou-16 crewed mission. That launch to the Tiangong space station could take place as soon as May 27. China earlier this month sent the Tianzhou-6 cargo spacecraft to Tiangong to provide supplies, propellant, science experiments and equipment to Tiangong.

Commercial company Landspace also recently delivered its second Zhuque-2 methalox to Jiuquan.

Andrew Jones covers China's space industry for SpaceNews. Andrew has previously lived in China and reported from major space conferences there. Based in Helsinki, Finland, he has written for National Geographic, New Scientist, Smithsonian Magazine, Sky...