What are the sources for the photometric data in NED?
A.: Most of NED’s detailed photometric data are taken from the larger catalogs, though we have also loaded many shorter lists from the journals as well. The Basic Data for each object, displayed on the Object Search Results pages, are from heterogeneous unreferenced sources, typically measured in the optical or near-infrared part of the spectrum (see the previous question). The data displayed on the Photometric Data Search Results pages are fully referenced. These data may apply to any part of the spectrum from gamma rays to radio. • Q.: Have the photometric data in NED been transformed or reduced in any way? A.: NED displays its collection of detailed photometry in two ways. First, the “data as published” and enough information to understand and use them are given. Then, NED applies the appropriate flux conversion factor, if needed, to reduce the published data to a common set of MKS units: W/m2/Hz (1 Jy = 10-26 W/m2/Hz). NED has adopted effective wavelengths, band widths, and absolut
