China has successfully launched the world's first quantum communication satellite - Quantum Experiments at Space Scale (QUESS) - from the Jiuquan Satellite Launch Center in northwestern Gobi Desert at 17:40 UTC on August 16, 2016 (01:40 local time on August 17).
After it enters a sun-synchronous orbit at an altitude of 500 km (310 miles), the 600 kg satellite will circle our planet once every 90 minutes. The satellite is nicknamed "Micius," after a fifth century B.C. Chinese philosopher and scientist who has been credited as the first one in human history conducting optical experiments, the Chinese Academy of Sciences (CAS) said.
QUESS is designed to establish "hack-proof" quantum communications by transmitting uncrackable keys from space to the ground, and provide insights into the strangest phenomenon in quantum physics - quantum entanglement, Xinhua reports.
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.
In its two-year mission, QUESS, is expected to beam entangled photons to two earth stations, 1 200 km (740 miles) 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.
Quantum experiments at space scale. Credit: NSSC
"The newly launched satellite marks a transition in China's role from a follower in classic information technology (IT) development to one of the leaders guiding future IT achievements," said Pan Jianwei, chief scientist of QUESS project with the CAS.
The scientists 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 like defense, military and finance.
One of the strange properties of quantum physics is that a tiny particle acts as if it's simultaneously in two locations - a phenomenon known as "superposition." The noted interpretation is the thought experiment of Schrodinger's cat - a scenario that presents a cat that may be simultaneously both alive and dead.
By harnessing quantum entanglement, the quantum key technology is used in quantum communications, ruling out the possibility of wiretapping and perfectly securing the communication.
A quantum key is formed by a string of random numbers generated between two communicating users to encode information. Once intercepted or measured, the quantum state of the key will change, and the information being intercepted will self-destruct.
In addition to quantum communications, there are quantum computers that have also drawn attentions from scientists and governments worldwide. Scientists say that a quantum computer will take just 0.01 second to deal with a problem that costs Tianhe-2, one of the most powerful supercomputers in the world, 100 years to solve.
If large-scale quantum computers are ever built, they will be able to crack all existing information encryption systems, creating an enormous security headache one day. Therefore, quantum communications will be needed to act like a "shield," protecting information from the "spear" of quantum computers, offering the new generation of cryptography that can be neither wiretapped nor decoded.
"If China is going to send more quantum communication satellites into orbit, we can expect a global network of quantum communications to be set up around 2030," said Pan.
Featured image: QUESS launch, August 16, 2016, China. Credit: Xinhua/Jin Liwang