The Double Quasar

Ever seen a gravitational lens? At magnitude 16.5, The Double Quasar is a magnitude brighter and much easier than Einstein's Cross. Just starhop 14 arcminutes NNW of 11th magnitude NGC 3079 in Ursa Major. The quasar's position at the western corner of a small "dipper" asterism makes it easy to spot the exact location. Its two components are oriented N-S and separated by about six arcseconds. Can you split them?


I have quite a bit of experience at observing QSO 0957+561A/B (the Double Quasar) in UMa. I first found this object using a 25-inch scope at TSP ' 95. Once I nailed the location using a wide-field photo of the area, the quasar(s) were actually easy to see and definitely elongated at medium to high powers. The very next night (when the seeing got very steady for TSP), I observed the pair in the 36-inch scope at 653x! There was enough black space between the two images to drive a Mack truck through (after all, it is 6" of separation)! Furthermore, you could actually tell which was the brighter of the two images at the time (one was at 17.1 and the other was at 17.4, if I remember correctly). When compared to other stars around the field, the quasar images actually looked slightly "nebulous" and had an eerie blue hue to them. It was quite a thrill...

Anyway, I can find them pretty easily in my 16" Starmaster; however, they do not split easily. They definitely appear elongated and "odd" looking, but the seeing must be near perfect as well as the transparency in order for me to make a decent split. A friend of mine has spotted the object(s) with a 14.5" scope. - Jay McNeil


I asked Jay if there were any other gravitational lenses that might be observable in amateur scopes:

Hmmm... Let's see, from my personal list there is--

The Leo Double Quasar (QSO 1120+019 A/B)

A is @ 11 23 20.8 +01 37 46 and is an easy 15.7 v mag
B is @ 11 23 20.54 +01 37 53.1 and is a not-so-easy 20.1 v mag
z=1.477
I tried for this last year at TSP with a 36-incher. The A component was not difficult, however, the B component didn't happen. Both components, however, displayed quite nicely on an enhanced DSS print that I have and used for the observation.

The Cloverleaf Quasar in Bootes (H 1413+117A/B/C/D)

A is @ 14 15 46.29 +11 29 42.7
B is @ 14 15 46.34 +11 29 42.9
C is @ 14 15 45.26 +11 29 43.4
D is @ 14 15 46.31 +11 29 43.7
z=2.558
All components of this bad boy are an acceptable 17th v mag; however, the greatest separation amongst the four is about 1.36"! Can you say OUCH!?! Saw the four as a very faint and indistinct single object in a 25-incher at some obnoxiously high power at TSP last year. Didn't exactly knock my socks off, though - if you know what I mean. Likewise, it shows up quite nicely as a pretty distinct "blob" on the DSS.

The Canes Venatici Twin Quasar (HE 1216+5032A/B)


A is @ 12 18 41.1 +50 15 34 and glows at 17.2 v mag
B is @ 12 18 40.4 +50 15 40 and glows at 19.0 v mag
z=1.451
This pair is separated by a whopping 9.1". However, only component A was obvious in the 25-incher.

Anyway, this was a little project of mine that never quite got completed (and I'm not very easily discouraged). I spent about a week gathering every piece of info I could on every known/highly suspected lens system that was within practical limits. The list came down to some 10 objects, and you now know of the top 5! Needless to say, these things just ain't that damn pretty! - Jay McNeil