Quasars and Other Active Galaxies. In this chapter you will discover…. 5-10% of galaxies unusually bright, called active galaxies The most distant objects we can see: quasars Evidence for unusual spectra and small volumes Models of quasars Tests of those models closer to the Milky Way
The luminosity can vary by as much as the entire brightness of the Milky Way Galaxy!!
635 Million light years away, and still one of the brightest radio sources in the entire sky!
These lobes are swept back because the galaxy is moving through an intergalactic medium.
X-ray isblue; radio is red
Superbright Elliptical Galaxy
A peculiar Star-like object, emitting lots of radio waves? But not with a stellar spectral fingerprint!
Quasars must be some of the most powerful objects we know of in the universe!
1.2 x 109 M for NGC 4261
3 x 109 M for M87
…which is at the center (nucleus) of the galaxy.Quasar Energy Source?
magnetic fields in accretion disks are twisted
they pull charged particles out of the disk and accelerate them like a slingshot
particles bound to magnetic field; focused in a beam