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The Question

(Submitted July 06, 2010)

Your page on active galaxies says that quasars are AGNs viewed down the jet. How does this reconcile with images of 3C273 which clearly show the jet shooting off to the side?

The Answer

I'm not sure what page you are referring to specifically. Generally, blazars are the quasars that are viewed jet on, while quasars are very bright and compact AGN. So a quasar such as 3C273 which has a visible jet is not a blazar.

It is important to remember that in the case of AGN (and to a certain degree astronomy in general), naming was often done based on observed qualities rather than an understanding of the physical nature of things (which was only understood later) so some naming schemes aren't perfect or particularly clear.

John and Mike
for "Ask an Astrophysicist"

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