
Astronomers Creep Up to the Edge of the Milky Way’s Black Hole - digital55
https://www.quantamagazine.org/astronomers-creep-up-to-the-edge-of-the-milky-ways-black-hole-20181030/
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yourapostasy
This brings to my mind Isaac Arthur's lecture "Civilizations at the End of
Time: Iron Stars" [1]. He posits that a Kardashev Scale 3 civilization might
use a galactic black hole to survive 10^100 entropic years of what he calls
the "Black Hole Epoch". Hearing about this possible giant blob of plasma
orbiting our galactic black hole makes me wonder if he and his team can come
up with plausible explanations that the plasma is actually some construct of
such a civilization, like perhaps a "construction site generator" as they're
building their "bunker against entropic time" amongst the black hole.

The really neat part of the lecture is towards the end, in his description of
time winding down into thermodynamic equilibirum, a Boltzmann Brain
fluctuating out of the equilibrium's randomness, and restarting the universe
with another Big Bang. That's fascinatingly close to universe origin stories
in Abrahamic religions, and echoes Hindu religious cosmological cyclicality.
One aspect I didn't see touched upon is the possibility that our universe and
we are simulations inside that Boltzmann Brain. And then there are the
arguments that we do _not_ want Boltzmann Brains [2].

Now if only the religious adherents in all our nations duking it out against
other humans for not having the "right" religion could turn their cognitive
surplus (poured into their religion) outwards to helping illuminate more upon
these near-metaphysical physics challenges, we might actually get somewhere.
After all, our best guess at the moment is we're halfway out of time in the
universe.

[1]
[https://www.youtube.com/watch?v=Pld8wTa16Jk](https://www.youtube.com/watch?v=Pld8wTa16Jk)

[2] [http://www.preposterousuniverse.com/blog/2013/08/22/the-
higg...](http://www.preposterousuniverse.com/blog/2013/08/22/the-higgs-boson-
vs-boltzmann-brains/)

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_cs2017_
The title would be a great sentence to test the quality of machine
translation.

~~~
Odenwaelder
"Astronomen schleichen sich bis an den Rand des Schwarzen Lochs der
Milchstraße"

Perfect german translation.

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Hei1Fuya
A decent translation, but maybe not quite idiomatic. Herantasten or annähern
instead of schleichen feel more appropriate.

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pontifier
The strawberry seed apparent size comparison stopped me cold. That's
incredibly tiny, and I'm in complete awe at this feat of humanity.

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gmiller123456
It's not the size of something that makes it visible, but its brightness.
Without actually doing the calculations, I'd bet there are stars you can see
with your naked eye that are similar in apparent size or even smaller. In
order to see detail, you'd need a lot of magnification. But your eye or a
camera are able to detect that "something" is there due to the fact that there
a lot of photons coming from that direction. The article talks about them
observing dips in brightness, so they were probably just looking at a single
pixel, or a handful of pixels at best.

~~~
pontifier
They described seeing a change in position at that scale. Brightness is one
thing, but detecting an angular change like that is mind boggling.

It feels like you'd have to start compensating for things like plate tectonics
and daily variation in the earths rotation due to melting glaciers to get that
kind of accuracy.

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teh_klev
Direct link to paper:

[https://www.aanda.org/articles/aa/pdf/forth/aa34294-18.pdf](https://www.aanda.org/articles/aa/pdf/forth/aa34294-18.pdf)

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stephengillie
> _Astronomers call it Sagittarius A_ * _(pronounced “A-star”)._

Why do astronomers call the black hole "A Star" when they know better than
anyone else that it's not a star, but a black hole?

Why don't we call it "Sagittarius A-black hole"?

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scentoni
The asterisk has nothing to do with indicating it is a star.

> The name Sgr A* was coined by Brown in a 1982 paper because the radio source
> was "exciting", and excited states of atoms are denoted with asterisks.

[https://en.wikipedia.org/wiki/Sagittarius_A*](https://en.wikipedia.org/wiki/Sagittarius_A*)

