Black holes

stoneill

Black Holes are detectable by the x-ray emissions along the axis of rotation.
I can understand that the disc of spinning material build more and more energy as it approaches the event horizon, radiating energy in higher and higher wavelengths until it goes through the whole spectrum to x-rays.

So here's me question - Black hole - nothing escapes, how does the x-ray emission escape?

Rubecula

Nothing escapes is not quite right really.

Ever had indigestion from eating too much too quickly? Well think of a Black Hole as a big stomach (not a great analogy I know) Well when a black hole starts gulping things down it sometimes takes in too much at once and simply can not swallow fast enough ..... so the poles are where it 'belches' this give rise to some black holes, sometimes, letting out an almighty beam of x-rays.

Not a good analogy as I said but it is a simple way to explain it.:)

rccaulfield

Do you mean quasars? My understanding of them is that the source of the x-rays is from the event horizon and before it not from the black hole- http://en.wikipedia.org/wiki/Quasar

Rubecula

I didn't actually mean Quasars in my explanation but they are a good if massive example of the phenomenon. I am not sure but I am under the impression that Quasars relate more to Super Massive Black Holes in very distant parts of the universe, I do stand to be corrected on this though.

squonk

Thanks! I had the same thought watching Wonders of the Universe myself. I'd often thought 'If nothing escapes Black Holes, how does the XRay energy get out' but then forgot! thanks for answering that!

Capt'n Midnight

stoneill wrote: »

So here's me question - Black hole - nothing escapes, how does the x-ray emission escape?

nothing escapes once it passes the event horizon (ignoring the way BH's evaporate)

other than that think of it as splashback

peterako

And remember....it's a theory....and 'we don't understand the physics' fully yet

Rubecula

My car is a good example. It is a black hole for money. I put a lot in and nothing comes out but I know it is there. (Trite but to the point)