The International Space Station ISS demonstrates long-term international cooperation between many partner
governments as well as significant engineering and programmatic achievement mostly as a compromise of budget,
politics, administration and technological feasibility. A paradigm shift to use the ISS more as an Earth observation
platform and to more innovation and risk acceptance can be observed in the development of new markets by shifting
responsibilities to private entities and broadening research disciplines, demanding faster access by users and
including new launcher and experiment facilitator companies. A review of worldwide activities shows that all
spacefaring nations are developing their individual programmes for the time after ISS. All partners are basically still
interested in LEO and human spaceflight as discussed by the ISECG. ISS follow-on activities should comprise clear
scientific and technological objectives combined with the long term view on space exploration. This includes key
competences like robotics, internal and external space structures, module/facility and experiment operations as well
as supply systems (e. g. ATV). Giving financial feasibility priority, DLR started to investigate future low cost
options by evaluating various LEO infrastructure concepts including opportunities for national realisation and
international cooperation. Scientists and users from various disciplines were involved to assess the usability of
corresponding options. Proposed payloads were based on their Mir and ISS experience with respect to future
scientific fundamental and technological research questions. Together with US and European industry, NASA and
ESA astronauts, operation specialists, current ISS users and scientists, DLR conducted an extensive concept study
using the DLR Concurrent Engineering Facility (CEF).
The present paper describes the results of these activities with a Phase A design called Orbital-Hub based on a
small low cost manned LEO platform including a man-tended free flyer. The first flying H/W components could be
realised in the frame of moderate budgets in the next eight years. The Orbital-Hub would guarantee a smooth
transition between ISS and further space activities in and beyond LEO and would represent an important step
regarding long-term space research, Earth observation respectively monitoring and human space exploration.