BEIJING — China’s quantum communication satellite, launched last August, is officially operational after four months of in-orbit testing, the Chinese Academy of Sciences (CAS) said Jan 18.

Testing of the satellite, payloads and space-ground links have been completed, the CAS said, adding that everything was operating properly.

The Quantum Experiments at Space Scale (QUESS) satellite is the first-ever space-ground test platform for quantum communication, said Wang Jianyu, executive deputy chief engineer of the project.

The research team has begun to carry out experiments and preliminary data has been obtained, said Pan Jianwei, chief scientist on the project.

China successfully launched the world’s first quantum satellite from Jiuquan Satellite Launch Center on Aug 16, 2016.

QUESS will explore “hack-proof” quantum communications by transmitting unhackable keys from space, and provide insight into the strangest phenomenon in quantum physics — quantum entanglement.

Composite photo taken on Dec 9, 2016 shows a satellite-to-earth link established between quantum satellite “Micius” and the quantum teleportation experiment platform in Ali, Southwest China’s Tibet autonomous region. [Photo/Xinhua]

Photo taken on Dec 10, 2016 shows a satellite-to-earth link established between quantum satellite “Micius” and the quantum teleportation experiment platform in Ali, Southwest China’s Tibet autonomous region. [Photo/Xinhua]

Photo taken on Nov 25, 2016 shows a telescope at the quantum communication ground station in Xinglong, North China’s Hebei province.[Photo/Xinhua]

Quantum satellite “Micius” flies past the quantum teleportation experiment platform in Ali, Southwest China’s Tibet autonomous region, Dec 9, 2016. [Photo/Xinhua]