China launches mobile telecom satellite

A Long March 3B rocket takes off with the Tiantong 1-02 communications satellite. Credit: Xinhua

A new Chinese mobile communications satellite launched Thursday on top of a Long March 3B rocket, joining a similar spacecraft launched four years ago to provide voice and data services to users on the go.

The Tiantong 1-02 mobile communications satellite lifted off at 1559 GMT (10:59 a.m. EST) Thursday from the Xichang satellite launch center in Sichuan province of southwestern China, according to the China Academy of Launch Vehicle Technology.

The launch occurred at 11:59 p.m. Beijing time.

A Long March 3B rocket carried the Tiantong 1-02 satellite into orbit.

The 184-foot-tall (56-meter) rocket shed its four hydrazine-fueled strap-on boosters, a core stage, and a second stage in the first few minutes of the flight, then a cryogenic upper stage ignited two times to deploy the Tiantong 1-02 spacecraft into an elliptical, or egg-shaped, orbit.

Tracking data released by the U.S. military indicated the rocket placed the Tiantong 1-02 spacecraft into an orbit ranging between 105 miles (170 kilometers) and 22,257 miles (35,820 kilometers) above Earth, with an inclination of about 28.4 degrees to the equator.

Chinese officials declared the launch a success, and the Tiantong 1-02 spacecraft is expected to circularize its orbit in the coming days using its own propulsion system. The satellite will settle into a circular geostationary orbit more than 22,000 miles over the equator, where its velocity will match the speed of Earth’s rotation.

A statement released by the China Aerospace Science and Technology Corp. — the top state-owned contractor for China’s space program — said the Tiantong 1-02 satellite will join the Tiantong 1-01 satellite launched in 2016 to form an S-band mobile communications system.

Similar mobile satellite networks, such as the commercial Inmarsat system, include hand-held terminals for subscribers to connect from remote locales. Users on the Tiantong network also employ small handsets.

The Tiantong network is “independently developed and constructed” by China, and allows users to connect with voice communications and message and data services across China, other parts of the Asia-Pacific region, the Middle East, and Africa, according to CASC.

The mobile communications network, which operates will also serve users in most areas of the Pacific Ocean and Indian Ocean, officials said.

China Telecom, China’s third largest mobile network provider, operates and markets Tiantong satellite communications services.

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