China launches world's 1st quantum satellite

China on Tuesday launched theworld's first quantum satellite, which will help it establish"hack-proof" communications between space and the ground, statemedia said, the latest advance in an ambitious space programme.

The programme is a priority as President Xi Jinping hasurged China to establish itself as a space power, and apart fromits civilian ambitions, it has tested anti-satellite missiles.

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The Quantum Experiments at Space Scale, or QUESS, satellite,was launched from the Jiuquan Satellite Launch Centre in theremote northwestern province of Gansu in the early hours of Tuesday, the official Xinhua news agency said.

"In its two-year mission, QUESS is designed to establish'hack-proof' quantum communications by transmitting uncrackablekeys from space to the ground," it said.

"Quantum communication boasts ultra-high security as aquantum photon can neither be separated nor duplicated," it
added. "It is hence impossible to wiretap, intercept or crackthe information transmitted through it."

The satellite will enable secure communications betweenBeijing and Urumqi, Xinhua said, referring to the capital of
China's violence-prone far western region of Xinjiang, where thegovernment says it is battling an Islamist insurgency.

"The newly-launched satellite marks a transition in China'srole from a follower in classic information technology
development to one of the leaders guiding future achievements," Pan Jianwei, the project's chief scientist, told the agency.

Quantum communications holds "enormous prospects" in thefield of defence, it added.

Messages that can't be wiretapped, cracked

If the tests are successful, China will take a major step toward building a worldwide network that can send messages that can't be wiretapped or cracked through conventional methods.

"It moves the challenge for an eavesdropper to a different domain," said Alexander Ling, principal investigator at the Centre for Quantum Technologies in Singapore. "Lots of people around the world think having secure communications at a quantum level is important. The Europeans, the Americans had the lead, but now the Chinese are showing the way forward."

Quantum communications use subatomic particles to securely communicate between two points. A hacker trying to crack the message changes its form in a way that would alert the sender and cause the message to be altered or deleted.

Researchers around the world have successfully sent quantum messages by land. But a true satellite-based network would make it possible to send quickly encrypted messages in an instant around the world and open the door to other possible uses of the technology.

Cybersecurity has been a major focus in recent years for China, which has pushed regulations aimed at limiting technology imported from the U.S. in the wake of Edward Snowden's revelations of widespread surveillance by the U.S. through the use of American hardware.

China has in turn been repeatedly accused by the U.S. of hacking into computer systems to steal commercial secrets and information that could harm American national security. China has rejected claims that it runs a state-sponsored hacking program and says that it is among the leading victims of cybercrime.

Quantum messaging could become a major defense against hackers and have applications ranging from military and government communications to online shopping.

The biggest challenge, Ling said, is being able to orient the satellite with pinpoint accuracy to a location on Earth where it can send and receive data without being affected by any disturbances in Earth's atmosphere. The results of China's tests will be closely watched by other research teams, he said.

"It's very difficult to point the satellite accurately," Ling said. "You're trying to send a beam of light from a satellite that's 500 kilometres (310 miles) above you."

Future global standard?

Hoi Fung Chau, a professor and quantum communications researcher at Hong Kong University, said that it was too soon to say if the tests will succeed, but added he expected quantum messages by satellite to become the global standard eventually.

"The theory is already there, the technology is almost there," he said. "It's just a matter of time."

The launch is a major triumph for China, which has spent years researching quantum technology and developing the satellite and other uses for it. China has previously announced the construction of a quantum link between Beijing and Shanghai that would be used by government agencies and banks.

China insists its space programme is for peaceful purposes,but the U.S. Defense Department has highlighted its increasingspace capabilities, saying it was pursuing activities aimed toprevent adversaries from using space-based assets in a crisis.

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