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Black Holes or Black Hole Stars? Astronomers Spar over 'Little Red Dots'

98 pointsby jandrewrogerslast Friday at 3:47 PM51 commentsview on HN

Comments

jahnuyesterday at 2:42 PM

One thing worth noting is our popular notion of what a star seems to be is quite different from what astronomers have.

One example, Canis Majoris has a radius of about 1420 solar radii. But its mass is roughly 17±8 times the mass of the Sun and therefore an average density of 5.33 to 8.38 mg/m3. “It is over 100.000 times less dense than Earth’s atmosphere at sea level.”

https://en.wikipedia.org/wiki/VY_Canis_Majoris

https://nineplanets.org/vy-canis-majoris/

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benji-yorkyesterday at 4:20 PM

Any decent human being would have called these Black Hole Suns.

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JumpCrisscrossyesterday at 4:19 PM

Is there an experiment that could resolve this? Literally resolve these objects better, or otherwise distinguish between these hypotheses?

Is there anything behind these objects they could lens?

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joebigyesterday at 10:32 PM

Wouldn't objects this ancient (following in the wake of the big bang, essentially) be redshifted anyway, on account of cosmological expansion?

itsalwaysgoodyesterday at 8:03 PM

Perhaps they are somehow related to the elusive white hole: exit points of black holes.

Fuel for a Big Bang, if you can imagine. A universe within itself.

The article says they're sucking up gas though so I don't know. The arrow of time is weird. It would feel elegant to me, but I'm way out of my league.

The imagined scenario only works if you picture all black holes 'twisting time' towards its beginning.

Sort of like recursion, or a tesseract, where there's one beginning and many endings.

ck2yesterday at 4:20 PM

Dr. Becky take: https://www.youtube.com/watch?v=KuTVjuXu7uE

PBS Space Time: https://www.youtube.com/watch?v=FMdrD_jcYgE

love those channels

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debo_yesterday at 2:11 PM

Soundgarden was apparently prophetic with their hit song "Black Hole Sun."

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