A Chinese satellite launched Tuesday will test the viability of data links that cannot be eavesdropped on, potentially leading to a revolution in defense communications.
The satellite carries a so-called quantum system, which sends a series of single photons to receiving stations on Earth. Any attempt to intercept the beam destroys it.
"The idea is to use quantum information stored in the state of a photon to transmit an encryption key between parties," quantum physicist Andrew Truscott of the Australian National University said by email.