Last satellite in Beidou network to launch

A key launch mission for China's Beidou Navigation Satellite System will take place on Tuesday, according to the China Satellite Navigation Office.

The Beijing-based office said in a statement on Monday evening that a Long March 3B carrier rocket will lift the final satellite in Beidou's third-generation network from the Xichang Satellite Launch Center in Sichuan province.

The launch was originally scheduled for the morning of June 16, but the mission command decided to postpone it several hours before ignition due to a technical problem with the rocket.

The statement said that the problem has been resolved and the launch will be conducted in due course. It did not give more details.

Sources close to the mission said the launch is very likely to take place in the morning out of consideration of factors pertaining to the launch window－a period of time suitable for launching a rocket.

The problem that caused the mission's postponement was "a minor one", sources said, adding that mission command needed to resolve all possible uncertainties to ensure the mission's complete success.

Once placed in orbit, the satellite, the 59th in the Beidou family and 30th in the third-generation series, will work with other Beidou satellites to allow users around the globe to access high-accuracy navigation, positioning and timing services.

The deployment will mark the completion of the Beidou network, China's largest space-based system and one of the four global navigation networks, along with the United States' GPS, Russia's GLONASS and the European Union's Galileo.

Since 2000, when the first Beidou satellite entered orbit, 58 satellites, including the first four experimental ones, have been launched. Some have since been retired.

Beidou began providing positioning, navigation, timing and messaging services to civilian users in China and other parts of the Asia-Pacific region in December 2012. At the end of 2018, Beidou started to provide global services.

Currently, there are 29 third-generation Beidou satellites in three types of orbit－24 in medium-Earth orbit, three in inclined geosynchronous satellite orbit and two in geostationary orbit.

There are also some second-generation Beidou satellites in operation, offering regional services.