
Astronomers report most distant blazar ever observed - pseudolus
https://phys.org/news/2020-03-astronomers-distant-blazar.html
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netcraft
> The beam of a blazar is only visible along a narrow line of sight. If the
> Earth is not within that line of sight, they are easily recognizable by
> astronomers. Thus, detecting objects can be extremely difficult (and
> fortuitous).

I don't really understand the "is not within" in that second sentence. They're
easier to see if we aren't in the line of sight?

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okramcivokram
Yes, I also noticed that. I think it should be either "not within -> not
easily recognizable" or "within -> easily recognizable".

~~~
aliceryhl
It's correct (but misleading) as is, actually. It's the kind of object that
sends a beam out, and if you're being hit by the beam, it's hard to recognize,
but by looking at it from the side, it becomes easier.

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lacker
This article was useful to me because I learned that a "blazar" is a thing.

 _Blazars are one of the brightest of a class of objects called active
galactic nuclei (AGN), which are supermassive black holes (SMBHs) in the
centers of galaxies. They are active due to the presence of a disk or sphere
of ionized gas around them which "fuels" the emission seen at many
wavelengths. Blazars emit powerful relativistic jets bright enough to be seen
across the universe._

