Astro 21.3 - Means source must be less than a few light...

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Astro Chapter 21 Section 3 Quasars and other Galactic Nuclei Active galactic nuclei – bright galactic centers Quasars are the brightest active galactic nuclei Most powerful is 1000x MW Quasars - Energy output from gigantic accretion disk surrounding supermassive black hole with a mass millions to billions of times that of our Sun. - discovered in 1960s - emission lines of hydrogen were hugely redshifted - the Quasar, 3C 273 has luminosity about 10^39, 10^12 times that of our sun - Hundreds of times luminous than entire milky way - located in center of galaxies or clusters - most lie more than halfway to cosmo horizon - produce lots of EM waves from infrared to gamma ray Active galactive nuclei must be smaller than 100 light years across. Radiowave images show that its less than 3 light years across Occasionally the luminosity of active galactic nucleus doubles in a matter of hours
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Unformatted text preview: Means source must be less than a few light hours across In other words, its generated in a volume of space not much bigger than our solar system Radio galaxy-active galactic nucleus is power source-drives two jets of particles outwards in opposite directions at nearly c-shoot far beyond bounds of stars in galaxy-the place where jets ram into gas show up as hot spots within radio lobes-basically the same as quasar What power quasar and other active galactic nuclei?-super massive holes-stuff ffalling in is converted into KE and collisions between falling stuff turns from KE to Thermal energy-an amount of matter greater than Sun pass through accretion disk and falling into black hole each year to produce so much luminosity-faster rotation of black hole release more energy-radiation not from hole but from accretion disk around it...
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Astro 21.3 - Means source must be less than a few light...

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