Black Hole Found That Takes Up 14% of Its Galaxy's Mass

An anonymous reader sent word that astronomers have discovered an absolutely enormous black hole residing in a galaxy that seems too small for it. In a new study (PDF), researchers looked at galaxy NGC 1277 and found that its central black hole weighed in at roughly 17 billion solar masses. Quoting Phil Plait: "The problem is, that’s far more massive than the central bulge of NGC 1277 would suggest the black hole should be. It’s well over half the total mass of the bulge! In fact, the entire mass of the galaxy is about 120 billion solar masses, which means the black hole at its heart is 14 percent of the total galaxy’s mass; compare that to the Milky Way’s black hole mass of 0.01 percent and you’ll see why astronomers were shocked."

Comments

Missing from the summary

[mcgrew]

It's the largest black hole they've yet found, if the article I saw yesterday is correct.

It might be easier to study since it's so big

[voislav98]

I wonder if, with a black hole as large and relatively less shielded, you can look for some evidence of relativistic effects around it.

That's not a galaxy...

[idontgno]

that's an accretion disc.

Visualization of how large NGC 1277

[rminsk]

From redditor xSmoothx post titled "Putting into perspective just how big the black hole of NGC 1277 truly is"

Re: Visualization of how large NGC 1277

[Baloroth]

And, interestingly enough, given the mass and size of the hole, air at sea level is about 19 times more dense than the black hole is. Black holes are just strange.

Re: Visualization of how large NGC 1277

[turbidostato]

"But the mass is not distributed over that volume. inside the black hole the mass is actually contained in an infintesimal point"

Ahh! the old problem... equations versus reality!

All that the Einstenian equations tell us is that they don't know how to manage black holes beyond the event horizon (and that they are wrong about them because of that).

Given that the event horizon neatly divides the universe in two, it is perfectly reasonable to say that the black hole density (from the outer univese perspetive) averages its overall percieved mass by its volume.

At the very least it's clear that a black hole must have "density significantly higher than that of a neutron star."

Because?

All you can say is that *if* (a big if) black holes behave more or less like all the physics we know about, there must be something within the black hole with densities above those we can find on a neutron star because by all we "common sense" know, black holes are like neutron stars, only more so.

"Saying it's less dense than the air is misleading in that respect."

What's misleading about saying density is defined as mass against volume?

still waiting for 1 trillion+ solar masses...

[PJ6]

I read (I think it was in 'death by black hole') that the more massive the black hole, the less gravity you experience at the event horizon. For a 1 trillion mass black hole, supposedly it would only have 10g at its event horizon. For still greater masses, you could have 1g, something reasonable for both a human and a spaceship to deal with... in theory, you could hover a ship with a person in it at the very boundary of such an event horizon... how sharp would this boundary be? I'd lower a string to see where and how it gets clipped.