Quantum-satellite leap by China

China launched the world's first quantum-enabled satellite early Tuesday, the first step in building a space-based quantum communications network that is virtually uncrackable.

The 631-kilogram satellite, which is named after the ancient Chinese philosopher and scientist Micius, lifted off at 1:40 am atop a Long March 2D rocket from the Jiuquan Satellite Launch Center in Northwest China.

It will operate 500 kilometers above the Earth's surface for at least two years, circling the globe every 90 minutes.

It is the third in a row of firsts for the Chinese Academy of Sciences' space science satellites. The launch follows the Dark Matter Particle Explorer satellite that will help scientists deepen their understanding of the past and future of galaxies and the universe, and the Shijian 10, which carried out experiments in microgravity physical and life sciences, according to the academy.

The satellite is designed to establish "hack-proof" quantum communications by transmitting uncrackable keys from space to the ground and to provide insights into the strangest phenomenon in quantum physics - quantum entanglement.

Quantum communication boasts ultra-high security, as a quantum photon can neither be separated nor duplicated. It is hence impossible to wiretap, intercept or crack the information transmitted through it.

With the help of the new satellite, scientists will be able to test quantum key distribution between the satellite and ground stations and conduct secure quantum communications between Beijing and Xinjiang's Urumqi.

As planned, it will also beam entangled photons to two earth stations, 1,200 kilometers apart, in a move to test quantum entanglement over a greater distance as well as test quantum teleportation between a ground station in Ali, Tibet, and itself.

"The newly launched satellite marks a transition in China's role - from a follower in classic information technology development to one of the leaders guiding future IT achievements," said Pan Jianwei, chief scientist of QUESS project with the Chinese Academy of Sciences.

The scientists now are expecting quantum communications to fundamentally change human development in the next two or three decades, as there are enormous prospects for applying the new generation of communication in fields such as defense, military and finance.

Research has shown that it is practically impossible to crack, intercept or wiretap quantum communications because its physical traits mean it cannot be replicated, separated nor reverse-engineered.

Any attempt to interfere with its transmissions will leave a mark, disrupt the communication and result in parties involved being warned.

In addition to China, researchers in Austria, Germany, Singapore, Britain, Canada and Italy also are developing quantum-enabled communications technologies, they said.

Contact the writer at zhaolei@chinadaily.com.cn