Gravitationally lensed quasar 2M 1134-2103

[Robin]

Hi everyone,

This morning I observed the gravitationally lensed quasar 2M 1134-2103 (a.k.a. J1134-2103 or 2MASS J11344050-2103230) with my 20" Dobsonian at 419x magnification. I couldn't find anything about this object here on Deepskyforum.

It was discovered on Gaia DR2 data and independently on PanSTARRS images in 2018/2019:
https://www.aanda.org/articles/aa/pdf/2018/10/aa33480-18.pdf
https://academic.oup.com/mnras/article/486/4/4987/5484879

It is located in the Crater constellation at RA = 11h34m40s, DE = -21°03'23", total magnitude 15.65 mag (17.2, 17.3, 17.3, 19 mag components at 4" maximum distance from each other) and its redshift is z = 2.77, which means 11.3 billion years light travel time.

For me it is located very low in southern direction, so it was much more difficult than Andromeda's parachute. With averted vision I intermittently saw a stellar object. Nothing elongated and I could not resolve anything.

Please find attached my sketch.

Has anyone of you observed this? Were you able to see an elongated shape or could you resolve anything?


Clear skies

Robin

5307

[Howard B]

Excellent observation Robin! How were the observing conditions - I imagine that transparency was quite good, yes?

[Robin]

Hi Howard,

Thank you! I din't determine limiting magnitude exactly, but I think it was average for the location, perhaps about 6.5 NELM at zenith. However, it was a bit hazy towards the horizon. 15.65 mag would have been much easier at zenith. That's why I wonder if people at southern latitudes with good seeing observed some more detail, such as an elongated shape.

Clear skies

Robin

[ScottH]

Before your post late last year, Robin, I had this one on my list of FOUR lensed quasars to chase down in Crater. And of the three I managed to see in my 16-inch a few nights ago, 2M 1134-2103 was the brightest and easiest to see at 300x. In fact, it's got me wondering if I could see it in my 10-inch! As to what it looked like, the seeing didn't allow me to go beyond 300x...otherwise I would've tried to look for elongation.

Scott H.

P.S. You mention a combined magnitude for the members, but for what it is worth, you forgot to mention that it was their combined 'G magnitude'. I don't think 'V magnitude' and 'G magnitude' are the same...