Hellenic Space Dawn: Selene & Helios: Geosystems Hellas (GSH) together with EMTEC Space P.C., ISD S.A., ΗΕRON Engineering, LEO Photonics, AUTH, UoA and HNA, are creating the first Greek CubeSat twin constellation SELENE and HELIOS (CubeSat for Earth monitoring, high-Level Mission instrument), the Hellenic Space Dawn (ESA ITT AO/1-11498/22/UK/ND). The project partners design, build, test, launch and operate the two HS-DAWN cubesats (CubeO-1 και CubeO-2). The two cubesats carry Remote Sensing imaging instruments for Earth observation, and have a capability of 5 times a day revisit and 1 night-time acquisition.