The Ultimate First Light?

[Guest]

Fantastic find (and very lucky)

https://www.independent.co.uk/news/science/universe-beginning-astronomy-picture-space-telescope-a8720016.html?utm_medium=Social&utm_source=Twitter#Echobox=1547072469

[robin_astro]

Actually That  article is a little misleading, particularly the title. (I wish they would give a reference in these articles to the original work. Here is a link to the paper  https://arxiv.org/abs/1810.11924  )

This is neither the most distant quasar detected (There are ~150 known at this distance or further at redshifts > 6, the most distant at z=7.5) or the first one found which is gravitationally lensed.  Gravitationally lensed quasars and galaxies are quite common, though this is the first lensed quasar seen to date beyond redshift 5.   

The significance of this work  is that there may be a significant number of  gravitational lensed quasars further than z=6  that have previously been overlooked which could bias how bright we think quasars are at this distance

Cheers

Robin

 

[Guest]

1 hour ago, robin_astro said:

This is neither the most distant quasar detected (There are ~150 known at this distance or further at redshifts > 6, the most distant at z=7.5)

 

I can find info on 15 quasars at z>6.  Please provide your source for 150.  My source is going through https://bit.ly/2TKRJ3t

[robin_astro]

12 hours ago, Sland said:

I can find info on 15 quasars at z>6.  Please provide your source for 150.  My source is going through https://bit.ly/2TKRJ3t

Your link leads to a google search, not a reference. 

The ~150 figure comes from the introduction in their paper which I linked, though I have not followed up their provided reference

"Luminous quasars at z > 6 allow detailed studies of the evolution of supermassive black holes (SMBHs) and the intergalactic medium (IGM) at early cosmic times. To date, ∼ 150 quasars have been discovered at z > 6, with the highest redshift at z = 7.54 (Banados et al. ˜ 2018)"

Note none of these quasars at z>6 were  previously considered to have been gravitationally lensed. This new paper casts doubt on that. Many lensed high z quasars might have been missed

I find it is always a good idea to follow up these articles in the general press by looking at their source. Often the scientific story is quite different

Cheers

Robin

[robin_astro]

There is more on the consequences of this discovery in this paper

https://arxiv.org/abs/1810.12302

where they also quote a figure of ~150 for the number of quasars at z>6

[robin_astro]

This article in Space Daily is better, though  the word "absolute" should be added in front of "brightest". This quasar is certainly not the "brightest" or even I suspect the most luminous once account is taken of the gravitatonal lensing

http://www.spacedaily.com/reports/Astronomers_uncover_brightest_quasar_in_early_universe_999.html

Robin

[Demonperformer]

On 10/01/2019 at 00:18, robin_astro said:

I wish they would give a reference in these articles to the original work.

But that would severely restrict what they could say. No journalist is going to agree to that!