Black Hole Found Inside Globular Cluster

acidrain writes "Contrary to the prediction of some computer models, scientists have found a black hole resting peacefully in a dense nest of stars called a globular cluster. Previously discovered black holes are either similar in size to a large star, or super massive holes which are millions of times bigger than a star is able to remain stable. This finding indicates there may be an intermediate size range of holes residing within these star clusters."

Comments

Large by mass

[MillionthMonkey]

The singularity is a point but the Schwarzchild radius around it is directly proportional to mass. One earth mass is equivalent to something like a few cm of Schwarzchild radius.

Inside the Schwarzchild radius everything falls into the hole regardless of velocity, no exceptions.

warning required?

[PTBarnum]

The important question is, does this black hole have a warning label?

WARNING: do not drop spaceship keys into black hole

I wonder if time is dilated there...

[Progman3K]

If you lived on a planet of the star closest to the black hole, would the passing of your time be measurably different from ours?

Re:I wonder if time is dilated there...

[shma]

According to General Relativity, the passage of time at a location depends on the gravitational field there. So, for instance, if the sun were to collapse into a black hole, there would be no change in the passage of time here. You would have to pass within a few Schwarzschild radii to see an effect (The Schwarzschild radius for the sun is about 3 kilometers, while Earth is 150 million km from the sum)

Re:I wonder if time is dilated there...

[rufty_tufty]

"The article says the black holes are "resting" inside the globular cluster"

Next you'll be telling me its pining for the fyords!

Re:Yet Another Black Hole

[cciRRus]

Actually there is just one; the rest were dupes. =)

Re:Black hole do not change their mass

[SuiteSisterMary]

(note: this is from memory)

Our sun is defined as 'one solar mass.'

Very basically, a star's tendancy to collapse in on itself is countered by the fact that it's a big old nuclear fireball. As it runs out of hydrogen to burn, it starts to collapse in on itself again, until it starts burning helium. Once the helium is gone, it starts to collapse again.

Any given star of less than 1.4 solar masses will stop collapsing and turn into a white dwarf, due to the fact that it's gravity isn't enough to overcome the repulsion of electrons. (If this white dwarf gets some new material, say, by having a red giant close enough that it can gather material from it, it will explode, giving us a supernova.)

Any given star of greater than 1.4 solar masses but less than 3 solar masses will overcome this, but get halted by inability to squish neutrons together.

Anything bigger than 3 solar masses will overcome neutron degeneracy, and collapse even further into a black hole.