Using On-Line Databases to Estimate the Galaxy Interaction Rate: Looking Forward to a National Virtual Observatory

The recently published UZC (Updated Zwicky Catalog; Falco et al. 1999, PASP, 111, 438) represents a major upgrade in positions and redshifts for the galaxies in the original ZC (Zwicky et al. 1961, and following). We have analyzed the multiplicity properties of the galaxies in the UZC (pairs, triples, and groups). Of the 19,000+ galaxies in the catalog, there are 1600 multiple systems with known redshifts z<0.08. We use this sample to estimate the Galaxy Interaction Rate in the local universe and to determine properties of the multiple galaxies. Archived data and astronomical catalog information available on-line from NASA's ADC (Astronomical Data Center) and from NED (NASA Extragalactic Database) are used to provide a firm physical basis for the interaction interpretation of these multiple galaxy systems. This project represents a typical research scenario that will be enabled through the implementation of a National Virtual Observatory (NVO). The envisioned NVO would be accessible from any astronomer's desktop. The data and metadata holdings of such on-line archives as ADC and NED will provide valuable information and database content for the NVO. The NVO will enable more complicated multi-spectral archival research investigations and cross-survey correlations with the impending multi-terabyte data avalanche coming from existing and future digital sky surveys (e.g., Sloan, 2MASS, DPOSS, NVSS, GALEX, FAME). (This research was supported under NASA contract NAS5-98156.)