China's new relay satellite to help video calls possible with space station

BEIJING - A new relay satellite launched late Sunday night will allow video calls to be made between China's future space station and the ground and provide data transmission and control services for various spacecraft.

The Tianlian II-01 satellite was sent into orbit at an altitude of 36,000 km by a Long March-3B carrier rocket from the Xichang Satellite Launch Center in Southwest China's Sichuan province on Sunday.

The satellite, developed by the China Academy of Space Technology (CAST) under the China Aerospace Science and Technology Corporation, will provide data transmission services for satellites operating on medium- and low-Earth orbit and monitoring and control support for the launch of spacecraft.

A relay satellite, regarded as the "satellite of satellites," is like a control station moved from the ground to space, experts explained.

"The Tianlian II-01 ushered in the construction of a new generation of the relay satellite system for China," said Zhang Peng, commander in chief of the research team of the satellite from CAST.

From 2008 to 2016, China launched four relay satellites to form the Tianlian I system, making China the second country in the world to establish a relay satellite system which is able to cover the whole world. The system can provide global real-time information transmission.

Last year, China sent a relay satellite, named Queqiao, meaning Magpie Bridge, into a halo orbit around the second Lagrangian (L2) point of the earth-moon system, nearly 500,000 km from Earth.

Queqiao plays a key role in ensuring the success of the Chang'e-4 probe to make the first-ever soft landing and exploration on the far side of the moon.

As the first satellite of China's second-generation relay satellite system, Tianlian II-01 is compatible with the Tianlian I system, but its transmission speed and volume and coverage area have been greatly improved, according to Zhang.

For instance, the transmission speed of the Tianlian II-01 doubles that of its predecessors and its design life has been extended.

The construction of the Tianlian II relay satellite system will improve China's space-based communication infrastructure, said Zhang.

The Tianlian II relay satellite system will also help service countries along the Belt and Road, Zhang added.