Final Beidou-3 satellite reaches operational orbit, China’s launch sites gear up for July missions

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HELSINKI — China’s final Beidou-3 satellite has reached its intended geostationary orbit and passed systems checks, a week after launch from Xichang.

The satellite’s frequency synthesizers, atomic clock, navigation processors and inter-satellite payloads and other systems are working normally, the China Aerospace Science and Technology Corporation stated in a June 30 release

The Beidou-3 GEO-3 satellite reached an altitude of around 35,786 kilometers above the Earth following five orbital maneuvers. It will orbit fixed over 110.5 degrees East. 

“Judging from the fixed-position capture that we had just completed, currently, the satellite orbit control is accurate with various parameters normal,” Liu Yuxiang, an engineer at the Xi’an Satellite Control Center, told state media.

“We will test the satellite platform and the inter-satellite links system in about a week, and the satellite will be officially connected to the network to provide services after each of its subsystems is fully checked”.

Launch took place June 22 and the satellite could enter into operation late July according to CASC. The satellite will complete China’s Beidou-3 system for providing global positioning, navigation and timing services.

As well as PNT services the Beidou system offers short message communication through its satellites placed in geosynchronous orbits.

The fully operational Beidou system consists of 24 satellites in medium Earth orbit, three in geostationary orbit and three more in inclined geosynchronous orbits. An earlier plan outlined a total of 35 operational satellites.

Apstar-6D , Tianwen-1 launch preparations

The Xichang Satellite Launch Center is now preparing for launch of the Apstar-6D communications satellite. Its launch via a Long March 3B rocket is expected around July 10.

Apstar-6D is owned by APT Satellite, a subsidiary of ChinaSat which belongs to CASC. It is based on the new DFH-4E platform and will feature a hybrid propulsion system. 

Launch of the high-throughput satellite was expected in 2019 but was delayed by the failure of the DFH-4E-based Zhongxing-18 (ChinaSat-18) in August 2019. 

The launch of Zhongxing-18 was successful, however attempts to communicate with the satellite did not succeed. According to an investigation by the satellite manufacturer the satellite suffered a complete power failure. 

The Yuanwang-5 tracking ship will assist the Apstar-6D mission, before heading to waters for the Tianwen-1 Mars mission launch. China is yet to announce a launch window or tentative launch date. Activity at the coastal Wenchang Satellite Launch Center however suggests to observers a launch date around July 23. 

China could also launch the first Kuaizhou-11 from Jiuquan in the northwest in the first half of July. The launcher, a solid rocket derived from missile technology, may lift as much as 1,000 kilograms to 700-kilometer SSO. The KZ-11 is, like the smaller KZ-1A, operated by Expace for commercial launches.

Jiuquan and the northern Taiyuan satellite launch center could also see further activity in July involving various remote sensing satellite. This could see all four of China’s launch centers could be in action during the calendar month.