- X-Ray Astronomy Group - University of Cambridge
Research of the group focuses on observational studies of active galaxies, clusters of galaxies, elliptical galaxies, and the X-ray background.
- Imagine the Universe!: Active Galaxies and Quasars
Information about Seyferts, quasars, and blazars.
- Chandra X-Ray Observatory: Quasars & Active Galaxies
Describes the general properties of these powerful phenomena located at the center of galaxies.
- Finding Charts for AGN
From the National Heidelberg Observatory.
- HEASARC: Active Galactic Nuclei
Photos and diagrams, spectra, light curves, and other information.
- ADC Quick Reference: Basic Data on Quasars and AGN
Provides data on quasars, Seyferts, BL Lac objects and optically variable QSOs, and other active galaxies, AGN, and emission-line objects.
- Quasars and Active Galactic Nuclei
Introduction to the subject of active galactic nuclei, with photos, spectra, and articles.
- Extragalactic Articles: Active Galaxies
Aggregation of papers on the subject of quasi-stellar objects, very luminous galaxies, and more.
- Active Galaxies Newsletter
Electronic publication dedicated to the observation and theory of active galaxies.
- Georgia State University: Program in Extragalactic Astronomy, The (PEGA)
Studies the astrophysics of active galactic nuclei (AGN) through photometry and spectroscopy.
- Active Galaxies & Quasars - Jodrell Bank Observatory
Researching neutral gas and dust in active galaxies, activity in starbursts and Seyfert galaxies, DRAGNs, gravitational lenses, and related matters.