Orome1 quotes a report from Help Net Security: In a new study, researchers from the Max Planck Institute in Erlangen, demonstrate ground-based measurements of quantum states sent by a laser aboard a satellite 38,000 kilometers above Earth. This is the first time that quantum states have been measured so carefully from so far away. A satellite-based quantum-based encryption network would provide an extremely secure way to encrypt data sent over long distances. Developing such a system in just five years is an extremely fast timeline since most satellites require around 10 years of development. For the experiments, the researchers worked closely with satellite telecommunications company Tesat-Spacecom GmbH and the German Space Administration. The German Space Administration previously contracted with Tesat-Spacecom on behalf of the German Ministry of Economics and Energy to develop an optical communications technology for satellites. This technology is now being used commercially in space by laser communication terminals onboard Copernicus -- the European Union's Earth Observation Program -- and by SpaceDataHighway, the European data relay satellite system. It turned out that this satellite optical communications technology works much like the quantum key distribution method developed at the Max Planck Institute. Thus, the researchers decided to see if it was possible to measure quantum states encoded in a laser beam sent from one of the satellites already in space. In 2015 and the beginning of 2016, the team made these measurements from a ground-based station at the Teide Observatory in Tenerife, Spain. They created quantum states in a range where the satellite normally does not operate and were able to make quantum-limited measurements from the ground. The findings have been published in the journal Optica.