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Bright lensed quasar discovered in Andromeda

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A quadruple gravitationally lensed quasar has been discovered in Andromeda - see https://arxiv.org/pdf/1705.08359.pdf and https://arxiv.org/pdf/1707.05873.pdf for images and details. It doesn't seem t

So now we need a chart     

Got it with the 12" frac last night just before 3am. I used magnifications of 215x (a 28mm Nirvana) and 300x (a 20mm Plossl) and could see it with both, but I don't think 300x made it any easier and t

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On 10/08/2017 at 01:28, harrym said:

The most amazing thing about this quasar is its redshift of 2.377, giving a distance of around 11 billion light years (at the time the light was emitted; it's now more like 19 billion). This means that if you manage to observe it, it may well be the most distant object you will ever see.

Just as amazing to me is that you can pop up the garden with a telescope and view it !


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17 hours ago, Littleguy80 said:

Amazing what can be seen. Forgive my ignorance, will the magnitude remain at that level or is there potential for it to get brighter? 

Quasars are often variable so it could change brightness, yes. But as it's only recently been discovered we don't know anything about its light curve.

It seems to have been recorded as a magnitude 14.9 'star' in some catalog (can't remember which one), whereas combining the magnitudes from the initial paper suggested 14.5, and visually it seemed more like 15.2. As these measurements were all at different times I guess this could be a sign of its variability?

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Just saw this quasar again. The conditions weren't nearly as good as last time, but I think it's a bit brighter now than it was in August. Back then it was fainter than the star I marked "14.9?" on my chart which I posted earlier in the thread, and I estimated it was around magnitude 15.2, but this time it was the same brightness as the 14.9? star or maybe even a little brighter - perhaps 14.8. Now's the time to give it a go before it gets fainter again!

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I wonder if this has been noted to Alex Wolf - of the Stellarium Developer's group. Who knows if it's already included? But no harm in sending him a 'heads' up' on this. Stellarium has a great many quasars noted as is. But I don't know if a 'quadruple-lensed' has been noted in it. Yet.

Fascinated -


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