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Largest Black Hole Measured
porkpickle tips us to a BBC article on the quasar OJ287, a binary object containing largest black hole yet discovered, weighing in at 18 billion times the mass of Sol. Researchers were able to estimate its mass due to the presence of a smaller black hole in orbit around it. When the smaller companion's orbit intersects OJ287's accretion disk, once every 12 years, it triggers a burst of radiation that was detected by the Spitzer Space Telescope. More detail and a diagram are available on the Turku University site.
How large can a singularity be?
I mean, if they used the word "massive" I'd get it. But large?
Proctologists across the globe swoon!
The simple truth is that interstellar distances will not fit into the human imagination
- Douglas Adams
Which one weighs 18 billion times our sun, and which ones weighs 100 million times our sun?
"Know but never fear the consequences of your actions."
That was serious, here's the link to the non-serious.More there...
mcgrew's razor: Never attribute to stupidity that which can be explained by greedy self-interest
My googling says its even more impressive (http://curious.astro.cornell.edu/question.php?number=31) 100 billion stars in the Milky Way and most are smaller than the sun, so 18 billion makes it very greedy indeed!
I pine for Sol, not a massive black hole. Otherwise, we'll have a massive cleanup job? Oh, wait...
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
Seems like /. is going down one of them two holes...
Seven Days with Ubuntu Unity
"largest black hole yet discovered, weighing in at 18 billion times the mass of Sol."
Yes, but how many Twinkies is that?
Vincent J. Murphy
Spandex Justice
A "black hole" is not a hole like in your cheese - it's just a very sloppy term for an actual object with a higher-than-usual mass. So high, that it swallows all the light it might emit otherwise and thus appears to be totally black. Due to it's (assumed) look it's been dubbed a "black hole", though it's not really a hole - and it probably wouldn't be too dark around it, too...
The Hawking Evaporation or just random stuff that's falling into it (gas, particles) should emit a considerable amount of light. Within the Event Horizon, of course, everything's pitch dark. So, the thing should actually look like a Space Donut.
I'm an infovore...
used miles instead of km for AU :-)
Why do people say 'sol' instead of 'sun'. Is there some fundamental difference, or are they just trying to sound smart?
This story makes me want to play gridwars2 again.
And again, and again...
factor 966971: 966971
One question I have about gravity and black holes is this: If nothing can escape the event horizon, how can gravity escape it? In other words, would objects outside the event horizon ever feel the pull of gravity from that which is inside the event horizon?
Using this illustration and my trusty piece of paper straight edge, I estimate the long axis of the orbit to be 21000 AU and the minor axis to be 16000 AU. Using Ramunjan's Approximation for the circumference of the elliptical orbit and converting to light years, I guesstimate the circumference of the orbit to be ~1.99 (call it 2) light years.
For a 12 year orbital period this means that the orbiting black hole is AVERAGING 1/6c (~49965km/sec, call it 50k km/sec)... meaning at periquaserion it's really booking! Much faster than The Dash!
Tom.
I think this finally means that we have a definition for the SI unit "fuck-ton."
Gifts for Geeks - Stuff that really matters!
Hawking: Homer, your theory of a donut shaped universe intrigues me
"Our opponent is an alien starship packed with atomic bombs. We have a protractor."
It could be argued that the singularity of a black hole is an impossibly dense star. In which case, it would still be a solar system. However, it would only be a solar system if it had planets orbiting around it. It is highly unlikely that a black hole would have planets orbiting it, as the planets would have insufficient mass to keep from simply falling in to the black hole, that is to say the overwhelming mass of the black hole would place the barycenter of the black hole and any accompanying planet well inside the event horizon, and the orbital velocity that would be required to prevent simply being sucked in would be nigh unthinkable. A pair of black holes orbiting each other would be a binary system, just like two stars orbiting each other.
A holer system.
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beware he who would deny you access to information, for in his mind he dreams himself your master
Furthermore, as the Earth-Sun barycenter is well outside the Sun's Schwarzschild radius, it would be outside the event horizon of a solar-mass black hole, too. Not that the location of the barycenter even matters to the stability of the orbit.
There are exoplanets — the first discovered, actually — known to orbit neutron stars, which are only 10-20 km in radius. There's no reason why planets couldn't orbit black holes too.
The existence of a single solar mass black hole has nothing to do with any of the facts I stated. They hold no matter what the mass of the black hole, so long as it's not comparable in size to the planet's orbit itself.
(FYI, the smallest known black hole candidates are about 3 solar masses, with a size of about 18 km in diameter, i.e., about half the size of a neutron star.)
"Today"?! How often do you feel the need to stare at a gaping anus?!?
Now that I think about it, I'm pretty sure everything I just said is completely wrong.
Actually, my understanding is that the most common stars in the galaxy are Red Dwarfs, and thus smaller than our sun. (Yup, NASA confirms: http://planetquest.jpl.nasa.gov/glossary/red_dwarf.html)
For those of you who don't know, the term "Sol" means "A whale's vagina."
Similes are like metaphors
No. If you try to create gravitational waves (or light waves) and sent them back out through the horizon, they instead fall into the singularity (albeit more slowly than you yourself do as you fall, so you still see them traveling away from you).