Slashdot Mirror
The Fate of the First Known Black Hole
sciencehabit writes "Cygnus X-1 bears its name because it was the first source of x-rays found in the constellation Cygnus. In 1971, astronomers discovered that the x-rays came from the direction of a bright blue star whirling around a mysterious dark object. They speculated that the x-rays were resulting from material being torn away from the bright star and falling onto the dark object, perhaps a black hole. This year, astronomers established that Cygnus X-1 does indeed harbor a black hole, a dead star whose great gravity lets nothing, not even light, escape. Now that result has inspired a forecast for the system's future: The black hole will swallow even more mass from an unfortunate star circling it, then likely dash away on its own when its companion explodes."
Run for your lives!
Never, ever, EVER bet against Rush. Ever.
Steven Hawking, I'm looking at you.
Welcome to the Panopticon. Used to be a prison, now it's your home.
I for one welcome our new gravitational overlord.
The mound is the hole's only natural enemy.
then does light also attract black holes?
that is, does light exert a gravitational force on other celestial entities?
then, the next question, how fast is that force of gravity propagated?
I think Steven Hawking's Speak and Spell should be auto tuned to Geddy Lee's High Falshetto.....
No, I didn't. Honest... I ran out of gas. I... I had a flat tire. I didn't have enough money for cab fare. My tux didn't come back from the cleaners. An old friend came in from out of town. Someone stole my car. There was an earthquake. A terrible flood. Locusts! IT WASN'T MY FAULT, I SWEAR TO GOD!
We at the Society for Extreme Alarmism take this opportunity to warn you of the impending end of the world! In only 12,000 years (Earth years, that is) the matter being sucked away from the blue star will cause it to explode. The same universal force that causes dropped toast to land butter-side-down will determine that this explosion will hurl the black hole on a direct collision course with Earth at about half the speed of light. Elementary mathematics proves that in only 24,000 years, then, a force more disruptive than Obamanomics will destroy the Earth!
Repent Now!
"The mind works quicker than you think!"
>> that result has inspired a forecast for the system's future: The black hole will swallow even more mass from an unfortunate star circling it
So basically, they're modeling based on our economy?
You actually don't have to be a complete kook to doubt that solar-mass bodies like Cygnus X-1 are black holes. There are all kinds of other hypothesized objects that they could be, including black stars, gravastars, fuzzballs, quark stars, boson stars, and electroweak stars. These are all long-shots, but they exist in certain reasonably well-motivated physical theories.
For skeptics, I believe the evidence is stronger that Sagittarius A* is a black hole than that Cygnus X-1 is. Sag A* is the supermassive black hole at the center of our galaxy. Sag A* has been proved by indirect but very strong evidence to have an event horizon, which is essentially the defining characteristic of a black hole. (A singularity without an event horizon would be something different; the big bang singularity is an example of that.) It may become possible in the near future to do direct imaging of Sag A*'s event horizon, which would be direct proof that it's a black hole. There are fundamental reasons why we will never be able to do anything like that with any other black hole besides Sag A*, using foreseeable technology.
Find free books.
Actually, the referenced paper says something else.
They specifically talk about the LIGO II http://www.ligo.org/ gravity wave observatory. And yes, they believe that a gravity wave can be detected without having the ability to detect individual gravitons as baryonic particles.
Also, for what it's worth, it'd be possible to check one way or the other for several billion dollars worth of equipment: three large masses arranged in a scalene triangle with laser interferometers acting as a target plane, with another mass to target the plane at an angle of about 45 degrees relative to the face of the plane would either demonstrate a time base variance between the target masses -- or not. You have to keep the target masses relatively close to each other.
The speed limit on the mass after the slingshot would be about 240,000 KPH. To overcome that problem and get higher speed (we need relativistic speeds for crossing the plane), you need two more masses: one the size of the mass you sling-shotted, the other relatively smaller. From the reference frame of the large and small mass, the are effectively being dropped together onto a stationary object at 240,000 KPH. This will be enough to catapult the smaller mass up to relatavistic speeds for collision with the virtual plane. We don't care if the large slingshot mass and the large target mass survive, we just want the momentum transfer. Here's a nice little demo of the process: http://www.physics.org/interact/physics-to-go/extra-bounce/index.html
--Terry
Invisible to telescopic eye
Infinity, the star that would not die
All who dare to cross her course
Are swallowed by a fearsome force
This Space Intentionally Left Blank
They specifically talk about the LIGO II http://www.ligo.org/ [ligo.org] gravity wave observatory. And yes, they believe that a gravity wave can be detected without having the ability to detect individual gravitons as baryonic particles.
Yes, and the existence of gravitational waves has already been proved indirectly by the Hulse-Taylor binary pulsar system, which is losing energy at exactly the rate predicted by general relativity. There is really no doubt about the existence of gravitational waves, either theoretically or empirically. LIGO is cool because it could open the door to a new way of doing astronomy, not because there is doubt about the existence of gravitational waves.
Find free books.
for she has the face of a horse
and the ass of an otter
she eats and eats and eats and eats
she's your fat mother.
Vag A* is the supermassive black hole at the center of our galaxy.
Anyway we are all dead soon or a later.
Recipes for USA bankrupt - http://tinypaste.com/0d66f dd = dollar deluge (printed in the infinity)
Man, that black hole is so big, it's even capturing the limelight.
So... if they were right about that... what does that mean for us in 101 years time?
It pays to be obvious, especially if you have a reputation for being subtle.
someone needs to redub Hawking's lines in this then
http://www.youtube.com/watch?v=zSgiXGELjbc
It pays to be obvious, especially if you have a reputation for being subtle.
They specifically talk about the LIGO II http://www.ligo.org/ gravity wave observatory. And yes, they believe that a gravity wave can be detected without having the ability to detect individual gravitons as baryonic particles.
Now my head hurts ... thanx
I thought nothing could escape a black hole, so how can it explode? An explosion requires escaping it. I'm asking this as a non-physicist :)
Mine hurts too. The idea that we might detect gravitons as baryons is particularly painful.
get your guns out, people...
ELOI, ELOI, LAMA SABACHTHANI!?
Completly off topic but I think it would be funny to hack Hawking's speech box so that in the middle of a speech it would say something like 'I like turtles' and then a complete rant about why :)
Might be cruel but funny IMO