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LIGO detects most massive black hole merger to date

(www.caltech.edu)
360 points Eduard | 2 comments | 14 Jul 25 20:06 UTC | HN request time: 0.463s | source
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WrongOnInternet ◴[14 Jul 25 21:27 UTC] No.44565549[source]▶
> the 225-solar-mass black hole was created by the coalescence of black holes each approximately 100 and 140 times the mass of the Sun.

Does this mean that 15 solar masses were converted into energy? Because that's a LOT of energy.

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aaronharnly ◴[15 Jul 25 00:27 UTC] No.44566715[source]▶
Let’s see — the Tsar Bomba nuclear weapon released the equivalent of converting about 2.3 kg of matter into energy (1).

One solar mass is about 2 x 10^30 kg, so round numbers this event released the same as 10^31 Tsar Bombas, which is … a lot of energy? That number is too big to be a good intuition pump.

Let’s try again: over the course of its entire lifetime of about 10 billion years, the sun will release about 0.034% of its mass as energy (2). So one solar mass of energy is about 3000 solar-lifetime-outputs.

So this event has released about as much energy as 45,000 suns over their entire lifetime. I’m not sure how much of the energy was released in the final few seconds of merger, but probably most of it? So… that’s a lot of energy.

(1) https://faculty.etsu.edu/gardnerr/einstein/e_mc2.htm

(2) https://solar-center.stanford.edu/FAQ/Qshrink.html

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steve_adams_86 ◴[15 Jul 25 19:46 UTC] No.44575085[source]▶
It's humbling to consider what an incredibly low-energy state we humans live in. The universe is capable of such immense energetic outputs. We're humming along at energy levels approaching zero compared to most bodies floating around in space. Crazy.
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1. conradev ◴[15 Jul 25 20:48 UTC] No.44575657[source]▶
If you consider orders of magnitude from the Planck scale all the way up to the observable universe, we are actually somewhere in the middle
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2. steve_adams_86 ◴[16 Jul 25 06:25 UTC] No.44579281[source]▶
I hadn't considered that! That makes me wonder... Is that likely to be true for most forms of life? I wonder if there's some physical constraint that makes this likely. I suppose I won't know in my lifetime. It's also probably not so significant that we're close to the middle; maybe it's just my ape brain finding significance in arbitrary figures.

If I were to guess before, I think I would have estimated humanity was in the lower 10%. I suppose I was mostly thinking in terms of the Kelvin scale.

It's fascinating to consider how staggering the scale goes in either direction, now. Absolutely bizarre.