Mysterious Rays

[steph]

http://science.nasa.gov/headlines/y2008/19nov_cosmicrays.htm

 

[Urwumpe]

A few hundred parsec is not close to the solar system. It is just relatively close compared to many other things.

As we have a stellar black hole already in 3500 LY distance (~1000 parsec), having one closer would be not too surprising.

 

[Woo482]

is that black hole close enough to suck are solar system in ?

 

[unussapiens]

Yes it is. Remember that even the atom furthest away from you is pulling you towards it, a black hole that is closer just has a much stronger pull.

 

[steph]

I think the dark matter possibility is the most exciting. I wonder whether they can discover anything about dark matter by studying the electron rays.

 

[Woo482]

Yes it is. Remember that even the atom furthest away from you is pulling you towards it, a black hole that is closer just has a much stronger pull.

ok but how far is it away ? close or far ?

 

[Urwumpe]

ok but how far is it away ? close or far ?

If it is a unknown stellar black hole, it is far away. The gravity well of such a black hole would be only 3 - 10 times larger as the gravity well of the sun - and the gravity well of the sun has 1 light year radius.

It can not capture anything outside it's gravity well, but it can influence objects.

 

[Woo482]

ok

 

[willy88]

Sorry to jump the gun, but is there any possibility it could be....

...ALIENS?

It sounds crazy, which it is, but maybe, just maybe, there is some alien spacecraft that has recently fired up and is scooting around our neighborhood.

 

[Bj]

...ALIENS?

:hunter:


:lol:

 

[Linguofreak]

is that black hole close enough to suck are solar system in ?

Yes and no.

Yes in that everything in the universe sucks everything else in. (Gravity)

No in that the gravity of a black hole isn't any greater than any other object of the same mass. The difference is that black holes fit alot of mass into a relatively small space, so they are much better at demonstrating that gravity gets stronger the closer you get to an object. (That's a bit of a simplification, but I think it should give you the general idea).

The zone of no escape for a black hole with the mass of the sun would start at about 3 km from the black hole. The innermost stable orbit would be around 6km, and the innermost unstable orbit would be around 4.5km.

For comparison, the radius of the sun is about 700,000 km. If you were 700,000 km from a 1 solar mass black hole, you wouldn't feel the gravity to be any different than if you were skimming just above the surface of the Sun. If you were 7,000 km from a 1 solar mass black hole, you wouldn't feel the gravity to be any different from skimming the surface of a 1 solar mass white dwarf.

A black hole with the mass of the Earth would have a zone of no escape about two thirds of an inch (1.7 cm) across (a third of an inch in radius). A cherry would probably be a fairly good approximation, though it might be a bit large.

In other words, you need to get very, *very* close to a black hole before you would get "sucked in." (Typical stellar black holes would be a bit heavier than the sun, say 3 to 10 times the mass, so a zone of no escape starting between 10 and 30 km away, which is still downright tiny in astronomical terms.)


-----Post Added-----

If it is a unknown stellar black hole, it is far away. The gravity well of such a black hole would be only 3 - 10 times larger as the gravity well of the sun - and the gravity well of the sun has 1 light year radius.

It can not capture anything outside it's gravity well, but it can influence objects.

I think you mean Hill Sphere, not gravity well.

 

[Urwumpe]

I think you mean Hill Sphere, not gravity well.

Is practically the same. The real border of the gravity well is usually very close to the Hill Sphere.

 

[RisingFury]

is that black hole close enough to suck are solar system in ?

I'll put it this way...... I'm not losing any sleep over it.