China Launches Quantum Satellite in Bid to Pioneer Secure Communications
BEIJING — China launched the world’s first quantum communications satellite from the Gobi Desert early Tuesday, a major step in the country’s bid to be at the forefront of quantum research, which could lead to new, completely secure methods of transmitting information.
Researchers hope to use the satellite to beam communications from space to earth with quantum technology, which employs photons, or particles of light. That type of communication could prove to be the most secure in the world, invulnerable to hacking. Scientists and security experts in many countries are studying the technology.
The satellite is expected to circle the earth every 90 minutes after entering orbit at an altitude of about 310 miles, according to a report by Xinhua, the state news agency.
China’s many high-tech scientific endeavors, including its ambitious space program, have enormous backing from the central government. The country’s 13th Five-Year Plan, an economic blueprint that was announced in March, listed quantum technology as a focal point for research and development.
Traditional communications satellites send signals using radio waves. But a quantum communication satellite uses a crystal that produces a pair of entangled photons whose properties remain entwined even as one is transmitted over a large distance. Messages could be sent by manipulating these properties.
An article about the Chinese program published by the journal Nature in July said any tinkering with quantum communications would be detectable, which is why the method is secure. “Two parties can communicate secretly,” the article said, and could be “safe in the knowledge that any eavesdropping would leave its mark.”
If China succeeds in its satellite launch, the article said, that could mean many more such Chinese satellites in orbit, “which will together create a super-secure communications network, potentially linking people anywhere.”
“But groups from Canada, Japan, Italy and Singapore also have plans for quantum space experiments,” the article said.
While the communication would be unbreakable, the data transmission rate would also, at least at first, be glacial, more akin to the telegraph than the internet.
The Chinese researchers hope to use the satellite and quantum communications to establish secure transmissions between two ground sites. In theory, the satellite can provide the connection between them. The first major link in China would be between Beijing and Shanghai, and might open this year, according to Xinhua.
The satellite, which weighs over 1,300 pounds, is called Quantum Experiments at Space Scale, or Quess, and nicknamed Micius, after a Chinese philosopher and scientist in the fifth century B.C.
Pan Jianwei, the chief scientist of the quantum satellite project, told Xinhua earlier that the overall project involved building four ground stations for quantum communication and one station in space for experimental quantum teleportation.
A 2012 article in Nature said Mr. Pan was in his early 30s when, in 2001, he set up China’s first laboratory for manipulating the quantum properties of photons.
“The lucky thing was that, in 2000, the economy of China started to grow, so the timing was suddenly right to do good science,” Nature quoted him as saying.