Blockchain startup SpaceChain today announced that it has received a €60,000 grant from the European Space Agency (ESA) to investigate the use cases of their satellite-based blockchain wallet system. Funding for the ESA “Startup Activity” fund will support SpaceChain's efforts to bring ultra-secure, multi-signature, distributed satellite networks into orbit. The company has tested blockchain nodes in space. The technology uses a three-signature system on the satellite, including two ground-based signatures and a third on-orbit signature. Each transaction requires at least two of the three signatures to complete.