Black Hole Feeding

[Roj47]

I have seen the images on documentaries whereby you see an image (IR?) of a planet with a spiral of material being dragged into a black hole over a period of time.

All life (should there have been any) would be gone due to the heat (I believe) amongst other things....

Given the image I saw it looks like the complete destruction and removal from existance of a planet/star could take light years?

I can not comprehend this as in my mind I see it like pulling the plug in the sink and everything goes pretty quickly.

Ok.... Every situation is different, but I kind of get bogged down reading the internet and Lamens Terms are needed.

Kind regards

[Raptor]

I have seen the images on documentaries whereby you see an image (IR?)

Lots of the images of Black Holes come from the X-Rays which they emit. Chandra X-Ray observatory

A doomed star ventured to close to a massive black hole. Once close enough, the star starts to feel extreme tidal forces, exerted by the black hole. These first stretch the star, then finally completely rip it apart. Part of the stellar debris is pulled toward the black hole. In the extreme conditions close to the "monster" the gas heats itself up enormously, to millions of degrees. Before disappearing into the black hole forever, it emits a brilliant flare of X-ray radiation - a "last cry for help" of the dying star.

Source

So you're right, every thing does heat up a lot.

Given the image I saw it looks like the complete destruction and removal from existance of a planet/star could take light years?

I can not comprehend this as in my mind I see it like pulling the plug in the sink and everything goes pretty quickly

Just to clarify, it looks like you think a lightyear is a measure of time, but it's really a measure of distance. It's the distance that light can travel in a single year (9.4605284 × 1015).

I'm not sure for certain, but I think it is a relatively quick process, comparing it to a plug is probably pretty accurate when you consider the scale of the objects.

Hope that helps.

[Roj47]

Thank you for the fast response and very helpful.

Glad to have found this site and forum.

Really struggling to comprehend all the information, but relishing the challenge of trying

kind regards

[Startraveler]

Given the image I saw it looks like the complete destruction and removal from existance of a planet/star could take light years?

I can not comprehend this as in my mind I see it like pulling the plug in the sink and everything goes pretty quickly.

Well, if it was just a single planet or star it might never fall in. Instead matter falling into black holes tend to find itself as part of an accretion disk--basically just a big cloud of matter circling the black hole. Black holes don't have a stronger pull than any other body of the same mass (the standard illustration is to point out that if the sun were replaced with a black hole of the same mass, none of the planets' orbits would change). So they're not really just drains in space that anything passing by will get sucked into.

Anyway, back to the point; the accretion disk has some angular momentum keeping it in orbit. If matter in it is going to spiral into the black hole then that angular momentum has to be carried off somehow; otherwise, everything will just orbit forever. There are some processes that handle this; magnetic fields from the black hole can cause turbulence in the accretion disk that results in friction in the disk as well as a wind blowing away from the disk. Obviously this all takes a little time which is why it isn't a near-instantaneous sink drain kind of effect.