Blackhole question?

Question

Ok...in the middle of every galaxy..theres a black hole right??? But if blackhole sucks in everything, including light, then why is the centre of the galaxy very bright? Like messier 81.

Answer 1

There is indeed a supermassive blackhole (SMBH) at the core of most galaxies, but they don't suck everything in only, things that come too close. The stars in the galactic centre are too far out to be pulled into the blackhole. There are some stars near the galactic centre that appear to be orbiting the SMBH but their orbits are stable. An active SMHB - an AGN -which powers quasars consumes mostly gas, not stars.

Answer 2

1) because there are a LOT of stars between the center and the outside ..

2) because stuff (like stars) falling into the central black hole heats up and starts radiating ..

Answer 3

Go read a book.

Answer 4

Black holes do not "suck in" everything.

They are called black holes because what falls in never comes back out (not even light), however their effect on the rest of the universe is the same as any other massive object.

Black holes (even very massive ones) are very small objects.  For example, our sun has a radius of almost 700,000 km (430,000 mi).  A black hole with the same mass would have a radius of 3 km (less than 2 mi).

So the "lack of light" of a black hole is not easy to see (being small).

Also because it is (relatively) small, and space is large, matter that does fall towards a black hole will usually miss it and start orbiting the black hole before falling in.  As it falls in, it usually forms an accretion disk.

As the matter in the accretion disk approaches the horizon, the tidal disruption gets bigger and bigger.  Any object is torn apart.  At some point, even atoms are torn apart by this force.  This means that the matter gets very, very hot.

Anything that is very hot gives off lots of light (and since the disk is still outside, we can see that light).  In fact, quasars are bright because of the light that comes off the matter before it falls into the black hole: that light can be (in some quasars) brighter than all the other stars, in that galaxy, put together.

Answer 5

I'm not an expert, however as far as i know,

there isn't a black hole at the centre of every galaxy. Black holes do not 'always' attract, and they certainly don't attract everything. They do attract light though, and as the light gathers between us and the black hole, it appears more and more bright.

Hope this helped.

Answer 6

Let's first figure out the "size" of the supermassive black hole at the center of our Milky Way. The "size" of a black hole can be defined as the distance from its central point out to its event horizon (that's the region outside of which stuff, including light, might or might not fall completely into the black hole). Doing all the math, our black hole would be some 1,780,000 kilometers in diameter (that's about 0.00000019 light years) On the scale of our galaxy, even in its relatively crowded central region, that diameter is extremely small. Any stars that don't get within 1.7-million kilometers of the black hole can continue on its merry way, shining all the while.

Answer 7

Nobody knows for sure they are black holes. It is just an assumption. No one ever actually seen one and the idea that they suck in everything is a little too far fetch to be believed.

Black holes are Quantum Physic theories.

First you take a fancy name then you work out some elaborate explanation to make it work.

Answer 8

No you got your info wrong. There is not a black hole in every Galaxy. Only a few contain it and the one that do have it  look very peace full and kind of foggy.

Answer 9

although we cannot see blackholes we can see what is around them, this is called the eccresion disk - it can be bright as it may contain radiation, and other light sources

the blackholes you refer to are supermassive blackholes - they are slightly different to other blackholes they are much larger and it is not clear how they were created, they seem to be tied in with the total mass of the rest of the galaxy

they are bright and when 'actively feeding' known as quasars this is whent the spew out some of their accresion disk giving off a lot of light & radiation etc

Answer 10

well, only the stuff thats (fairly) close to the black hole gets sucked in.

other, further objects, like stars, and even light will begin to orbit the back holes (they ARE being sucked in, but it takes a long time to be completely sucked)

the line between sucked in and not really is called the event horizon. not a good place to be.

then, objects even further, tend to keep orbiting, but its not orbiting the black hole alone, but more like "the collection of other objects" orbiting it.

as you can see, the glow in the middle is "the collection of other objects" dust, stars, some planets, and light. is pretty bright cause there's alot of it.

even orbit the collection of stuff and we're all the way on the edge.

we're not affected by the BH, but the ENTIRE center of the galaxy.

think of a bathtub drain.  near the drain water spins madly, but away from it, a rubber ducky could sit calmly for quite some time.