  We introduce a new visual analytic approach to the study of scientific
discoveries and knowledge diffusion. Our approach enhances contemporary
co-citation network analysis by enabling analysts to identify co-citation
clusters of cited references intuitively, synthesize thematic contexts in which
these clusters are cited, and trace how research focus evolves over time. The
new approach integrates and streamlines a few previously isolated techniques
such as spectral clustering and feature selection algorithms. The integrative
procedure is expected to empower and strengthen analytical and sense making
capabilities of scientists, learners, and researchers to understand the
dynamics of the evolution of scientific domains in a wide range of scientific
fields, science studies, and science policy evaluation and planning. We
demonstrate the potential of our approach through a visual analysis of the
evolution of astronomical research associated with the Sloan Digital Sky Survey
(SDSS) using bibliographic data between 1994 and 2008. In addition, we also
demonstrate that the approach can be consistently applied to a set of
heterogeneous data sources such as e-prints on arXiv, publications on ADS, and
NSF awards related to the same topic of SDSS.
