Thanks HW
More info via Google search but my take may help.
Quasars are thought to be galaxies like our own Milky Way but with gigantic blackholes at their core which suck in surrounding stars and gas down to a single point or 'singularity' but eject a brilliant beam of light - the 'final scream before oblivion'!
So brilliant are the beams-of-light, directed at earth by chance alignment, that they can be seen almost back to the BIG BANG creation of the universe some 13.6 billion years ago from backyard telescopes! 100,000 quasars have now been discovered and are distributed across the whole sky.
The remote quasars in the linked pic were imaged in the autumn of 1998 via a 30cm Meade XL200 with Starlight Xpress MX9 CCD camera. Included are two gravitationally lensed, by intervening 'invisible' galaxies, which either split the quasar into two i.e. Q0957+561 or like APM08279+5255, receding at 92% velocity of light and some 12 billion light-years away, brightened by a factor x20 to shine like 5 quadrillion suns - truly Lighthouses at the Edge of the Universe.
All galaxies are moving apart due to the expansion of the universe since the Big Bang and this can be 'seen' in the Doppler Shift of quasar's spectrum in a spectroscope. The 'z' value is a measure of recession of the quasar [from earth] as deduced from a shift of the spectral lines towards the red end of the spectrum - in the case of the Lynx quasar from the invisible far ultra-violet at 1000A into far red at ~7000A. Now that's really red-shifted and a few amateurs have successfully attempted these measurements !
Hybrid Mode
