ESA-ESRIN, the European Space Agency Centre for Earth Observation (EO), is the largest European EO data provider and operates as the reference European centre for EO payload data exploitation. EO Space Missions provide global coverage of the Earth across both space and time generating on a routine continuous basis huge amounts of data (from a variety of sensors) that need to be acquired, processed, elaborated, appraised and archived by dedicated systems. Long-term Preservation of these data and of the ability to discover, access and process them is a fundamental issue and a major challenge at programmatic, technological and operational levels.Moreover these data are essential for scientists needing broad series of data covering long time periods and from many sources. They are used for many types of investigations including ones of international importance such as the study of the Global Change and the Global Monitoring for Environment and Security (GMES) Program. Therefore it is of primary importance not only to guarantee easy accessibility of historical data but also to ensure users are able to understand and use them; in fact data interpretation can be even more complicated given the fact that scientists may not have (or may not have access to) the right knowledge to interpret these data correctly.To satisfy these requirements, the European Space Agency (ESA), in addition to other internal initiatives, is participating in several EU-funded projects such as CASPAR (Cultural, Artistic, and Scientific knowledge for Preservation, Access and Retrieval), which is building a framework to support the end-to-end preservation lifecycle for digital information, based on the OAIS reference model, with a strong focus on the preservation of the knowledge associated with data.In the CASPAR Project ESA plays the role of both user and infrastructure provider for one of the scientific testbeds, putting into effect dedicated scenarios with the aim of validating the CASPAR solutions in the Earth Science domain. The other testbeds are in the domains of Cultural Heritage and of Contemporary Performing Arts; together they provide a severe test of preservation tools and techniques.In the context of the current ESA overall strategies carried out in collaboration with European EO data owners/providers, entities and institutions which have the objective of guaranteeing long-term preservation of EO data and knowledge, this paper will focus on the ESA participation and contribution to the CASPAR Project, describing in detail the implementation of the ESA scientific testbed.