Modern approaches to science, to account for the reality of distributed and heterogeneous data, have introduced the concept of presenting discovery, access and use of that data through a virtual view of the holdings in strong preference to attempting to bring the data and metadata sources together in one place (the “if we only had one database for X” fallacy). This concept arose formally in astronomy (ca. 2000) but has spread significantly since. Hence, the notion of an observatory, as used in the astronomical sense, is metaphorical and in many instances, the term virtual laboratory – or virtual repository – may be more applicable. The DCVO has a multi-layered schematic block architecture. The lower layer represents a variety of existing or required DCO data sources; the second layer integrates scientific processing tools and applications in present use for DCO researchers, and also includes discovery and search services, product generation, and the integration of data. Most important, these integrated data products can be fed into the top level, which can produce visual and analytic applications and other aggregate analyses. All of these capabilities will be assessed in relation to DCO project needs. Development is via an evolutionary and iterative approach, which is needed to accommodate both common and diverse data science capabilities identified to date. RPI’s Tetherless World Constellation (TWC) has developed numerous successful eScience applications using a methodology we have formalized from studying science communities and determining requirements for supporting large-scale eScience efforts, aimed at trained scientists who needed to work in interdisciplinary settings. We have successfully deployed and refined this methodology in focused scientific communities – typically with user communities of trained scientists numbering up to the low thousands. The longest lived of the deployments of this methodology has been in place for six years and is an interdisciplinary virtual observatory focused around solar, solar-terrestrial, aeronomy and space physics topics – the Virtual Solar-Terrestrial Observatory. The methodology has been reused in a wide array of topic areas including volcanology, plate tectonics, and atmospheric responses to volcanic eruption, coronal imaging data available from observatories such as the Mauna Loa Solar Observatory, arctic sea ice, satellite and ground-based aerosol data, biological and chemical oceanography data, and more.