http://www.skyandtelescope.com.au 65HOWARD BANICH
remember if z = 1.871 meant the quasar was really close or
really far away.
Steve and Jimi instantly knew z = 1.871 meant that it was
really far away, though, and they both came up with the same
answer: its light-travel time was about 10 billion years.
That’s right, 10 billion years.
As interesting as Arp 284 had been, our attention was
suddenly riveted on the quasar. Using the DSS image on his
laptop, Jimi showed us the quasar’s position in comparison
to two field stars off the end of NGC 7715, giving us an idea
as to where to look for it through the scope. The quasar’s
designation, based on its 1950 coordinates, is somewhat
misleading. In epoch J2000.0, it’s at RA 23h 36 m 60 s, dec.
+02° 10′ 45 ′′.
Jimi was first up the ladder, then Steve, then me. And there
it was! We all saw it easily with averted vision. Just think,
10-billion-year-old photons in real time — the back of my
neck started to tingle as I felt the edges of my everyday reality
start to warp. All I could do was stare at this faint point of
light, letting the primordial photons stream into my left eye
as my brain tried to make sense of them. Ten billion years is
far too long for me to comprehend, but this unimaginable
span of time was breathtaking nonetheless. Not to mention
the light was coming from a supermassive black hole’s
relativistic jet on the other side of the visible universe, which
just happened to be pointed at us.
This is what I wrote in my notebook after my sketch:Best, most memorable view of the night. Wow, a quasar whose
light has taken 10 billion years to get here — and I could hold its
stellar image steady with averted vision. Holy moly... N7714
and 15 were astonishing, too, and much more detailed than I
saw in my 28-inch at the OSP in August. 8mm (609×) and
6mm (812×), 1:07 a.m., 21.45 SQM.We took several more turns at the eyepiece, and during my
last look I thought about how photons don’t experience time
— at the speed of light, time stops. In our frame of reference,
10 billion years has passed since these photons were emitted
by the quasar, while from the photons’ frame of reference,
they’re just suddenly here.
That seems impossible, but it’s a part of how spacetime
works on both its largest and smallest scales. Unfortunately,
my comprehension is stuck somewhere in between.Perspective
While Steve and I took a final look, Jimi did a quick search on
his laptop to double-check the quasar’s brightness. MegaStar
showed it was 18th magnitude, and Steve confirmed the value
the next morning by doing a more extensive search.
We eventually moved on because there’s only so much to
see in a faint star-like point. Even so, bumping up against the
limits of my comprehension was exhilarating. We went to our
next target with some reluctance.
How to compare the distances of the three objects that fitSGALACTIC GLOW In the author’s sketch made under dark skies
(SQM reading of 21.72) with a 0.7-metre reflector at 408×, a delicate,
circular smudge and an enigmatic line comprise Arp 284. The interacting
galaxies lie about 3 arcminutes north of 16 Piscium. South is up.◗Ever wonder what you’d look at if you got your hands
on a big scope? The author added more than a dozen
objects to his observing logs by the time he finished his
night. If you want to follow his trail, here are the blazes:
NGC 7731 & NGC 7732 (Zwicky’s Pierced Galaxy)
Shakbazian 84
Arp 13 (NGC 7448)
NGC 7463, NGC 7464 & NGC 7465
Shakbazian 362
VV 84 (NGC 7433 galaxy group)
Arp 284
2333+019
M77
NGC 1048
NGC 1049
Trapezium region of M42Looking through the Big Scope
- The Shakbazian catalog lists 377 groups of compact
galaxies detected on Palomar Observatory Sky Survey
(POSS) red plates (https://is.gd/Shakbazian). - The Vorontsov-Vel’yaminov catalog is at http://is.gd/
VVCatalog.