China team’s space laser breakthrough takes communication speeds to high orbit

Chinese scientists have reported a milestone in space laser communications, sustaining a high-speed, hours-long laser link with a satellite more than 40,000km (25,000 miles) above the Earth. The capability is seen as critical to future deep-space networks.According to the Chinese Academy of Sciences’ Institute of Optics and Electronics, which led the project, researchers used a 1.8-metre (6-foot) aperture telescope in Yunnan province to lock onto a geostationary satellite within four seconds.During the experiment, which lasted more than three hours, the laser link sustained uninterrupted data transmission at 1 gigabit per second (Gbps) in both directions, the Sichuan Observer reported on Tuesday.The research team described the result as a “leading breakthrough” in long-duration, real-time communication in high orbit, where the tiniest of pointing errors or shifts in the atmosphere can break the beam.Lead researcher Liu Chao said high-orbit satellite-ground communication was often unstable and brief, sometimes lasting only minutes. And while data travels quickly from satellites, signals from Earth are much slower, making real-time interaction difficult.“It’s like sending someone 10 messages and getting only one reply,” Liu told the Sichuan Observer. “It’s hard to have an efficient conversation that way.”11:05Space race elevates Asia in new world order Space race elevates Asia in new world order