In March of 2001 Brian
Skiff pointed out the discovery of a new, bright quasar. This
quasar is called PHL 1811 and is the second brightest known.
Only the famous, 12.8-magnitude, 3C 273 is brighter. With this
discovery there are now two quasars that are bright enough to be
detected in small or modest amateur instruments.
Quasars are apparently
the bright inner core of galaxies where a supermassive Black Hole is
accreting material. As the material orbits around the Black
Hole it is heated to great temperatures, producing an enormous
amount of energy. The brightness of most quasars is variable
over a relatively short period of days. This tells us that
they must be very small, because an object cannot vary in brightness
coherently faster than the time it takes for light to travel across
it.
PHL 1811 appears to
vary between about 13.5 to 14.0 magnitude, making it almost as
bright as its famous cousin when caught near maximum light.
The redshift of PHL 1811 is 0.192, which corresponds to a light
travel time of 2.4 Gyr (assuming H=65 km/s/Mpc and Omega = 0.1).
3C 273 has a redshift of 0.16, which corresponds to 2.0 Gyr.
What this number means is that when you look at PHL 1811, the light
you are seeing took 2.4 Billion years to reach your eye. That
is over half the age of the Earth!
Like all quasars, PHL
1811 looks like just another faint star in the eyepiece. Some
might gaze upon it as little more. But to others, it is the
idea of what we are seeing that is so appealing. We are seeing
light which has traveled such an enormous distance and time only to
end its journey to be captured by our eyes. As our eyes
capture the light, our minds capture concept of a supermassive black
hole. Perhaps the only idea more grand is that we are capable
of doing so at all. 
The field in an 6-inch f/8 at
50x. North is down and east is to the right.
Discovery reference: Astronomical
Journal, June 2001 (AJ, 121, 2889-2894 (2001))
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