Brain Busters

[Krupski]

In the spirit on the "Jet on a treadmill" physics comedy, I thought it would be fun to watch you Fizzy-Cysts grapple with a new concept, so here goes...

A black hole, a star that has the mass of one million of our sun has collapsed into a sphere the diameter of earth. It's mass and gravity are beyond comprehension. Now (take my word for it), a spacecraft can orbit ANYTHING if it has enough velocity.

So, assuming that the hellish radiation caused by matter falling into the black hole's event horizon does not penetrate your spacecraft, what do YOU see, feel or hear when you are in your ship, orbiting the black hole at a reasonable altitude (say, 1 AU* from the center of the black hole)?

Bonus question: Assuming you cannot be hurt in any way, say you fell toward the black hole and got stuck at the event horizon. As you look around, what do you see? More detail = more points.

Have fun, and more brain busters are upcoming!

(* 1 AU = 93 million miles... the distance from our sun to the earth)

[whiskeyman]

Krupski you forgot to include the direction of rotation.

[Full Otto]

[N/A]

I read somewhere that the larger the mass of a black hole, the farther from the mass is the event horizon. This being that the event horizon is a measure of gravity; nothing to do with the mass.
Thus, the farther the event horizon is away from the mass, the less "stretching" gravity will do on a mass at the event horizon. It's entirely possible that a person or ship would experience no abnormal "stretching" at the event horizon of a massive black hole, if the gravity puts the event horizon far enough away from the mass itself.

Now, if your black hole contains a mass the size of Earth, then it would be an enormous "singularity", so to speak, and the event horizon would be quite a long way from the mass.

If the mass and event horizon together were no bigger than Earth, it would be a small singularity, with a very close event horizon, and you'd get stretched and tore to pieces just by coming close to the event horizon.

Redefine your question giving us the info if you are talking about the mass being the size of Earth, or the event horizon being the size of Earth.

[Krupski]

I read somewhere that the larger the mass of a black hole, the farther from the mass is the event horizon. This being that the event horizon is a measure of gravity; nothing to do with the mass.
Thus, the farther the event horizon is away from the mass, the less "stretching" gravity will do on a mass at the event horizon. It's entirely possible that a person or ship would experience no abnormal "stretching" at the event horizon of a massive black hole, if the gravity puts the event horizon far enough away from the mass itself.

Now, if your black hole contains a mass the size of Earth, then it would be an enormous "singularity", so to speak, and the event horizon would be quite a long way from the mass.

If the mass and event horizon together were no bigger than Earth, it would be a small singularity, with a very close event horizon, and you'd get stretched and tore to pieces just by coming close to the event horizon.

Redefine your question giving us the info if you are talking about the mass being the size of Earth, or the event horizon being the size of Earth.

Sorry about the confusion. I just meant to say that the black hole is ginormously massive. The astronaut is in a stable orbit millions of miles above the event horizon with an eccentricity of nearly zero (i.e. almost perfectly circular).

[N/A]

I'm thinking you are telling us that witches have black holes?

I know they have cold tits...or was that bitches?
Damn, now I can't remember.

[NAPOTS]

I only studied newton physics so I can only offer a guess. I assume this distance is outside of the event horizon. I understand that if you were inside it even light speed wouldn't be enough to maintain orbit.

At the cg of your space craft you'd sense 0 g because your gravitational forces are in equilibrium but your probably going so fast that time slows down for you on the side facing away from the black hole you'll see things happen that normally take eons. Supernova, formation of new stars celestial objects moving at impossible speeds. You'll probably witness objects either being drawn into ar at least pulled toward the black hole. On the side of the black hole you'll see nothing. There might also be some strange gravity affects due to the massive difference in gravity between the parts of the craft, and you, that are closer to the center.

[NAPOTS]

If I did it right you need to be going 2.98E7 m/s

[Krupski]

I only studied newton physics so I can only offer a guess. I assume this distance is outside of the event horizon. I understand that if you were inside it even light speed wouldn't be enough to maintain orbit.

At the cg of your space craft you'd sense 0 g because your gravitational forces are in equilibrium but your probably going so fast that time slows down for you on the side facing away from the black hole you'll see things happen that normally take eons. Supernova, formation of new stars celestial objects moving at impossible speeds. You'll probably witness objects either being drawn into ar at least pulled toward the black hole. On the side of the black hole you'll see nothing. There might also be some strange gravity affects due to the massive difference in gravity between the parts of the craft, and you, that are closer to the center.

Very good. Your answers are correct. Now, tell me WHY there would be "massive differences" in gravity in places away from the center of mass.

And you did great describing how outside events, to you, would be greatly sped up.

Have you ever heard the "whoop" sound of the gravity waves created by two colliding black holes?

https://m.youtube.com/watch?v=QyDcTbR-kEA

Incredible to realize that the last few milliseconds of the collision the two black holes are orbiting each other tens of thousands of times PER SECOND!

Same thing with millisecond pulsars... something with the mass of hundreds to thousands of times the mass of our sun rotating at hundreds of times per second, creating an audio tone in a radio telescope!

The fastest one known so far rotates at 716 revolutions per second or 42960 RPM!!! and creating an audio tone near F sharp in octave 5!!!

A super dense ball of matter around the diameter of earth spinning at almost 43 THOUSAND RPM and with so much gravity that remains almost spherical and doesn't fly apart. Mind blowing!

[Krupski]

I'm thinking you are telling us that witches have black holes?

I know they have cold tits...or was that bitches?
Damn, now I can't remember.

I think he meant "black ho".