• IPAC



Hertzsprung-Russel diagram for Active Galactic Nuclei (HR4AGN): Using space and ground based ultraviolet, optical, and infrared images to find a correlation between the color and luminosity of gas emission and dust emission around supermassive black holes at the centers of galaxies.


Data from the Galaxy Evolution Explorer (GALEX), the Wide-Field Infrared Survey Explorer (WISE), and the Sloan Digital Sky Survey (SDSS) was used to construct color-magnitude diagrams for Type I quasars at redshift values of 0.1<z<0.5. This effort improved upon previous ones by increasing the sample size to more than 400 objects and by increasing the covered wavelength span from 0.25 microns to 22 microns. Color was plotted against absolute magnitude at a variety of wavelengths, from near ultraviolet to infrared. No tight correlations were found when comparing any of the UV or optical colors to the various infrared absolute magnitudes. However, a relationship was found using the NUV (GALEX) - z band (SDSS) color vs NUV (GALEX) absolute magnitude.

Participant Educator


Ms. Wendy Curtis

Waynflete School, Portland, Maine

Participant Educator


Participant Educator


Ms. Pamela Thompson

Monrovia High School, Monrovia, California



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