New evidence of massive black hole in our galaxy

Holy hugeness !

Astronomers believe it is four million times more massive than our Sun.

Chinese scientists said on Wednesday they had gathered evidence that shows a giant object in the center of our galaxy is a super-massive black hole.

Zhi-Qiang Shen and researchers at the Shanghai Astronomical Observatory captured radio waves emitted just beyond the edge of the mysterious object, known as Sagittarius A, with a system of 10 radio telescopes spread across the United States.

In a report in the science journal Nature they said it "provides strong evidence that Sgr A is a super-massive black hole."

news.yahoo.com...

Neat stuff.

Probably another good reason to become a space fairing race

A huge black hole in our galaxy is, indeed, news for astronomers and astrophysicists but, for me, it only raises my anxiety level. Let me see, we have errant comets and asteroids on collision courses with Earth, and then there is always the threat of gamma ray bursts. Oh, and let's not forget about the possibility of "kill shots" of ejecta from our own sun. So now we have a Big Black Hole to worry about.

Scientists have known about this for some time (Almost a decade) in the West atleast, I hope China knew about this before this.

www.sciencedaily.com...

Heres the same discover in 1998

I think its even been observed feeding on small amounts of matter already.

BTW benevolent tyrant nothing to fear from that blackhole its like 30,000-50,000 light years away from earth since we are on the outskirts of the Milkyway and this big mamma in at its center. The smaller ones we dont know about floating around the galaxy are the more dangerous ones IMHO

[edit on 2-11-2005 by ShadowXIX]

[edit on 2-11-2005 by ShadowXIX]

Wait a minute now. I could have sworn that was already discovered.

OH, Whew, thanks Shadow.

I thought I was having a massive deja vue for a moment there. But now I'm just as confused because in addition to Shadows link back to 1998, I found a more recent discovery of apparently the same black hole in 2002-2003.

chandra.harvard.edu...

This Chandra image of the supermassive black hole at our Galaxy's center, a.k.a. Sagittarius A* or Sgr A*, was made from the longest X-ray exposure of that region to date.

I must be missing something here. I can only think of about 2 explanations for the multiple "discoveries".

1. This area of the universe is very large, and there are several large black holes in the Sgr A location. The confusion stems from a lack of specific location perhaps?

Chandra / Harvard
In addition to Sgr A* more than two thousand other X-ray sources were detected in the region, making this one of the richest fields ever observed.

Or perhaps it is another known problem that is spreading farther than anticipated.





2. The enigma that is....... *drum roll please*

The Big Black Nothing



Congrats to wecomeinpeace!

Originally posted by ShadowXIX
The smaller ones we dont know about floating around the galaxy are the more dangerous ones IMHO

No, they're not. Most people have the common misconception that black holes are the vacuums of the universe (I think Hollywood had a hand in this) but this is simply not true. A black hole only has as strong of a gravitational pull as the star had that first created it. Simply put, if the Sun suddenly turned into a black hole, which it won't don't worry, life as we know it would end yes, but for a different reason. Earth would keep merrilly circling the new black hole Sun, but it would be far too cold without the Sun's radiant energy to support life.

We have absolutley nothing to fear from them.

ms

Not sure if this was true or not but i saw this on a documentry horizon i think (yes im a brit) that at the centre of every galazy is a blak hole which is what holds it together, or is casued by the concentration of energy at the centre of the galazy or something.

Does anyone out there realize that the black hole in sagittarius is 26000 llight years away. I have read here and there many hints to 26000 years being a mayan, or ancient history, relevence.

Now, what if, the black hole in Sagittarius does something like expand (like NASA says it is doing now) large enough to cause a reaction within our solar system, enough to "destroy the earth" and start life all over again as it has done in the past according to history theory.

Maybe the mayan calendar was developed either with the knowledge of it happening many times, or (for those alien guys) help from outside intelligence? Look at how much importance Sagittarius plays with the Mayan religion, and the milky way... where the Sagittarius is located. Also, Orion on the opposite side of the world in Egypt and the relevence of the Eye of Horus.

Sorry for the ramble, but when you look at a black hole off angle it looks like an eye. So what if the black hole in Sagittarius (which some say is the center of the universe) expands so large so as to appear like an eye in the sky, and its magnetic pull (or push) causes havoc here on earth. If so, then on Dec 21, 2012, we are in for a fantastic show.

Ask why the US is doing what it is right now. Hording as much oil as it can to store for when all hell breaks loose. Maachu Picchu is where it is because the sea levels rose 26000 and the survivors had to move where they could, up in the mountains, to survive.

So, find high safe land now and build into the rock!!!!

mod edit: syntax

[edit on 25-12-2005 by sanctum]

Let us hope we dont find anytime soon what its like inside that hole!

Has planet X been ruled out as a possibility?

I think we are all going to go out with a huge bang

Originally posted by blackpanther1967
Does anyone out there realize that the black hole in sagittarius is 26000 llight years away. I have read here and there many hints to 26000 years being a mayan, or ancient history, relevence. Now, what if, the black hole in Sagittarius does something like expand (like NASA says it is doing now) large enough to cause a reaction within our solar system, enough to "destroy the earth" and start life all over again as it has done in the past according to history theory.

Hmm, if it expanded enough to affect earth then, it would gut most of the galaxy. Astronomical observations don't support the theory that a black hole can expand. All the theory denies that they expand and contract as well.
A black hole is a single point, where the intense gravity has punched a hole in space-time - what we see is teh accretion disc of super hot gas spiralling around it called the torus.


Some super massive black holes in the center of galaxies

Originally posted by midgetstar

Originally posted by ShadowXIX
The smaller ones we dont know about floating around the galaxy are the more dangerous ones IMHO

No, they're not. Most people have the common misconception that black holes are the vacuums of the universe (I think Hollywood had a hand in this) but this is simply not true. A black hole only has as strong of a gravitational pull as the star had that first created it. Simply put, if the Sun suddenly turned into a black hole, which it won't don't worry, life as we know it would end yes, but for a different reason. Earth would keep merrilly circling the new black hole Sun, but it would be far too cold without the Sun's radiant energy to support life.

We have absolutley nothing to fear from them.

ms

1) Since our sun could never turn into a black hole(its simply not large enough), then its not really a issue

2) you are wrong anyway IMO, while initially the black holes strength is dependent on the parent stars mass, the acceleration of mass increase is also dependent...a "sun size" (assume its possible for a second) black hole would increase faster. I propose this is due to the proximity of "matter" and more specifically "dark matter".This is the opposite to what seems natural but its what ive discovered so far.

earth would cease to exist, a black hole cannot even support light (the light itself cannot escape as the escape velocity needed to leave the black holes gravity is past c(light speed)....bascially its forever colapsing on itself, you are correct in saying the earth will circle the black hole, but earth will speed up and up and up, untill it crossed the event horizon.

this is the subject of one of my major papers for my masters of astrophysics, so while yes im only making educated guesses(as most phyicsist's are), ive got pretty good data to back up my theory...since i worked on it for about 6months

[edit on 25-12-2005 by s13viper]

Originally posted by dgtempe
Let us hope we dont find anytime soon what its like inside that hole!

Has planet X been ruled out as a possibility?

I think we are all going to go out with a huge bang

Take 2 astronauts, about 50km from the "event horizon" of a black hole

already even that close they would start feeling the gravitational effects. (but not significantly)

one astronaut goes towards the event horizon , as he passes across it he radio's back the msg "this is getting dark" to the other astronaut saftely on the space ship.

the word "this" is heard instantly by the 2nd astronaut as it was radioed before crossing the event horizon

the work "is" is heard (quicky about 30seconds) but is stretched out, like its playing in slow motion

the work "getting" is heard but about 50 years later, and only the 1st half of the word..then the 2nd half another 100years later, the word is so stretched that its virtually unheard..this was 1-5cm after crossing the event horizon...(imagine running up a escalator goin down, u eventually get to the top but u have run 5 times the actuall distance of the trip)

the work "dark" is never heard - the gravity is so intense that the radio wave cannot escape, its still there (adding its mass like the astronaut) except the "escaltor speed" has increased to match your speed...u cant get to the top.


to the astronaut IN the black hole, it would sound to him like it took only those few seconds to say it, then shortly afterwards the intense gravity would turn him into a giant piece of spagetti before ripping him apart, not pleasent.....to a observer form the outside the process would appear to take forever(well in theory, since light cant escape u cant actually see it), but on the inside it was a painless microsecond death.To the distant observer, it appears that the object, falling slower and slower, approaches but never reaches the event horizon. The astronaut himelf might not even notice the point at which he crosses the event horizon, and will do so in a finite amount of proper time: it is a property of the light leaving from the vicinity of the hole that makes it seem as though the astronaut never actually reaches the horizon.

or another way of looking as it using only one astronaut

Imagine a hapless astronaut falling feet first radially towards the center of a simple Schwarzschild (non-rotating) black hole. The closer he gets to the event horizon, the longer the photons he emits take to escape from the black hole's gravitational field. A distant observer will see the astronaut's descent slowing as he approaches the event horizon, which he never appears to reach.

However, in his own frame of reference, the astronaut will cross the event horizon and reach the singularity, in a finite amount of time. Once he has crossed the event horizon he can no longer be observed from the outside universe. As he falls, he will notice his feet, then his knees, becoming increasingly red-shifted until they appear invisible. As he nears the singularity, the gradient of the gravitational field from head to foot will become considerable, and he will feel stretched, and finally torn by tidal forces: his feet will feel a much stronger gravitational force than his head. This process is known as spaghettification. The gradient becomes large enough, close to the singularity, to tear atoms apart. The point at which the tidal forces become fatal depends on the size of the black hole. For a very large black hole such as those found at the center of galaxies, this point will lie well inside the event horizon so the astronaut may cross the event horizon painlessly and live.Conversely, for a small black hole, those tidal effects may become fatal long before the astronaut reaches the event horizon.

I relied upon the Schwarzschild metric the kerr metric and Schwarzschild radius equations in my research.

as a matter of interest for our "sun to be a black hole its radius would have to be about 3km


planet X is still a possibility in IMHO, the timings match.....having said that 15billion km isnt very far, so we should be able to find it

[edit on 25-12-2005 by s13viper]

1. We have nothing to fear. First, space is big. REALLY big! You just won't believe how hugely, vastly, mind-blowingly big it is. I mean, you may think it's a long way down the street to the corner store, but that's just PEANUTS to space! Space is so big, bigness itself seems really "titchy", and not that much to be concerned about. In short, the chances of a black hole, any black hole, having any affect on our solar system is so far unlikely as to be impossible.

2. Midgetstar is correct, the overall mass and far-reaching gravitational changes no different than when the star was the old mass. What matters is when a person gets CLOSE to the star. Let's put it this way. If you were on one side of the sun, the matter in the parts of the sun close to you will have a greater affect on you than the matter on the side of the sun away from you. If the sun collapsed a bit (got smaller with no change in mass), then the front side will have the same pull, but the back side would have a stronger pull, as it's closer. However, from far away (in the same region as why an atom can be neutral, even though it has a negative and positive part), both sides affect you roughly equally. A Black Hole does this to a much greater degree - but the same principal applies to distance, so being far away has about the same effect.

3. Dark Matter has nothing to do with this. It's "Dark" because there's no light. That's it. It's not a mystical property. The Earth is Dark Matter - as from a far away observer it is a mass that cannot be detected (due to the interferring light from the sun). So everything that falls into a black hole is "dark".

4. Every major observed galaxy has a Super-Massive Black Hole "driving it". It's a gravitational anchor for the whole galaxy, and has masses varrying from ten thousand to almost a billion suns. It's friggin' huge. However, it's incredibly far away. Remember, it takes even LIGHT 4 whole years to travel to the nearest star from here! And there's about 100 billion stars in our galaxy. And we're practically on the out-skirts! That Black Hole is just wayyy too far away. If by some freak cosmic coincidence something actually happened, and we were sent spiralling into the center of the galaxy (only thing that could likely do that is a "collision" with another galaxy, or a near-passing black hole, neither of which is in any way likely... well.. except the galaxy-collision, but we got about a dozen billion years to worry about that), it would still take 50 million years for us to reach the centre! And about 25 million years before any excess radiation from the growing proximity of stars affected us.


So people, don't worry, we're not doomed. Super-Massive Black Holes are just really cool.

Originally posted by Yarium
2. Midgetstar is correct, the overall mass and far-reaching gravitational changes no different than when the star was the old mass. What matters is when a person gets CLOSE to the star. Let's put it this way. If you were on one side of the sun, the matter in the parts of the sun close to you will have a greater affect on you than the matter on the side of the sun away from you. If the sun collapsed a bit (got smaller with no change in mass), then the front side will have the same pull, but the back side would have a stronger pull, as it's closer. However, from far away (in the same region as why an atom can be neutral, even though it has a negative and positive part), both sides affect you roughly equally. A Black Hole does this to a much greater degree - but the same principal applies to distance, so being far away has about the same effect.

3. Dark Matter has nothing to do with this. It's "Dark" because there's no light. That's it. It's not a mystical property. The Earth is Dark Matter - as from a far away observer it is a mass that cannot be detected (due to the interferring light from the sun). So everything that falls into a black hole is "dark".

So people, don't worry, we're not doomed. Super-Massive Black Holes are just really cool.

never said we were doomed, you are still wrong(or didnt understand what i was saying) on points 2&3

i never said it was dark matter as a visual thing....look up what dark matter is...dark matter is the matter that cannot be seen or dectected (at least so far) nothing to do with the "matter" stuck inside the black hole, its only dark because light cannot escape as you said..however "dark matter" would explain ALOT ,not only in black hole formation but also in many of the other universe bound questions. Ill probably be doing my P.h.D on this very subject, and well it is only my proposal not fact as yet, could solve alot tho

anyway

take 2 black holes, one SUPER massive one and one "sun sized" one

The point at which the tidal forces become fatal depends on the size of the black hole. For the very large black hole this point will lie well inside the event horizon so the astronaut may cross the event horizon painlessly and live . Conversely, for the small black hole, those tidal effects may become fatal long before the astronaut reaches the event horizon.

smaller is no less deadly = fact

now, if the small "sun sized" black hole was in its current location, guess what our solar system would be "eaten" by it......how you say? angular momentum, as the small black hole spin faster and faster (which is what happens when a single star colapses into a black hole) it gains momentum, virtually tearing and dragging the space aorund it........its only a matter of time before mecury is engulfed, then as the black holes mass increases its momentum increases etc etc....untill there is no more matter close enough to engulf despite the large momentum.......if the gravity can hold the 9 planets then it would be after this point it would stop.....the black hole it self isnt nessecarily growing, just its mass and therefore gravity. i have no idea how long it would take.

you are exactly right about it only matters when u get "close" to it....but obviously you cant help it if it comes closer to you!

Oh, I never said that Earth wasn't screwed if the sun turned into a black hole. We would be - but for reasons other than getting eaten. Mercury would likely get eaten, maybe Venus. But even then, their masses are almost infintesimally smaller compared to the sun's (and subsequent black-hole's) mass - and so being eaten would likely not change the size/spin of the black hole by any significant amount.

As for Dark Matter, I realize that things like Neutrinos and other WIMPs can compose a lot of it, and that's why research into Dark Matter is still important, but I fail to see how it is important in this discussion on Black Holes

Originally posted by Yarium
1. We have nothing to fear. First, space is big. REALLY big! You just won't believe how hugely, vastly, mind-blowingly big it is. I mean, you may think it's a long way down the street to the corner store, but that's just PEANUTS to space! Space is so big, bigness itself seems really "titchy", and not that much to be concerned about. In short, the chances of a black hole, any black hole, having any affect on our solar system is so far unlikely as to be impossible.

Yet another Adams fan I see

The Earth is Dark Matter - as from a far away observer it is a mass that cannot be detected (due to the interferring light from the sun). So everything that falls into a black hole is "dark".

Incorrect. The earth is made of regular matter as the earth reflects light, which is also possible to observe from over a hundred light-years away with adaptive optics techniques. It's even theoretically possible to image individual continents on Earth Sized planets with a combination of Gravitational Lensing(I think not too sure it may be some other technique they use, gotta ask Cmdkeenkid on this one lol) and Adaptive Optics. Within 10 years as the next gen Ground and Space based telescopes come on line you shall see what I'm talking about

4. Every major observed galaxy has a Super-Massive Black Hole "driving it". It's a gravitational anchor for the whole galaxy, and has masses varrying from ten thousand to almost a billion suns. It's friggin' huge. However, it's incredibly far away. Remember, it takes even LIGHT 4 whole years to travel to the nearest star from here! And there's about 100 billion stars in our galaxy. And we're practically on the out-skirts! That Black Hole is just wayyy too far away. If by some freak cosmic coincidence something actually happened, and we were sent spiralling into the center of the galaxy (only thing that could likely do that is a "collision" with another galaxy, or a near-passing black hole, neither of which is in any way likely... well.. except the galaxy-collision, but we got about a dozen billion years to worry about that), it would still take 50 million years for us to reach the centre! And about 25 million years before any excess radiation from the growing proximity of stars affected us.

There is some debate to this. Some Astrophysists and Cosmologists believe that black holes don't exist at all. Some think they are merely very very dense Neutron Stars. I personally disagree as the evidence seems to be mounting but the debate is far from over on wether they exist or not.

Frankely it would make understanding the Universe alot easier if that were the case as we still can barely wrap our heads around the mathematics involved in a Singularity.

[edit on 25-12-2005 by sardion2000]

Originally posted by sardion2000
Yet another Adams fan I see

Yeah, I am . Is that a crime?

Originally posted by sardion2000

Incorrect. The earth is made of regular matter as the earth reflects light, which is also possible to observe from over a hundred light-years away with adaptive optics techniques. It's even theoretically possible to image individual continents on Earth Sized planets with a combination of Gravitational Lensing(I think not too sure it may be some other technique they use, gotta ask Cmdkeenkid on this one lol) and Adaptive Optics. Within 10 years as the next gen Ground and Space based telescopes come on line you shall see what I'm talking about

[edit on 25-12-2005 by sardion2000]

Sorry Sardion, but I'm still correct . You see, that's for within our own galaxy (and the super-good telescopes they're refering to are massive interferometres, which could detect a far away planet's composition and atmospheric structure - useful for looking for carbon-based life-telling signs, like oxygen).

You see, the idea for Dark Matter comes from trying to find the percentage of mass in the universe. The idea is that, since the universe is homogenous (the same) in all directions at a certain size, that taking a sample of the universe can give you a good estimate for the entire universe. So we do gravimetric studies to find out how much that area of the universe "weighs". Then we try to find out how much of the matter we can actually see. Unfortunately, it's a pitiful amount. Things like Nebulae (which is easy to see in our galaxy, but hard to see in a massive super-cluster 5 billion light years away), planets, neutrinos (and other WIMPs - Weakly Interacting Massive Particles), and Black Holes should account for a certain amount of the energy and "weight" of that is missing. The topic is called "The Missing Mass Mystery" - since we're still short of the mass needed to complete the puzzle!

For one, we don't know how common these black-body masses are (masses where the spectrum of light they give off is not visible), and so cannot factor them into the calculations - hence why they are considered part of Dark Matter. These are also called MACHOs (Massive Astrophysical Compact Halo Objects).

So while we may be able to detect things like Black Holes, Planets, WIMPs, and MACHOs - we do not know enough about them to perfectly account for them in the Missing Mass Mystery. We still try mind you, but we're still off. So, more studies on Dark Matter are looking for something else that we can't see, that must exist, have mass, yet cannot normally be seen. At the moment we're stumped.

However, this is where the concept of Vacuum Energy works in. You see, I kinda lied when I said doing Gravimetric Studies. I forgot. They actually measure the energy of the area - and give over most of that energy to stars and such. Vacuum Energy is the idea that space itself has an overall REPULSIVE force - a kind of cosmic anti-gravity. It's a quick fix solution right now if you ask me, and I seriously doubt that it's what's actually going on. However, in its current incarnation, it does pretty much fill in the Missing Mass.

Also I've heard some Physists talk about Dark Matter particles as if they were Ghost Particles in that they don't interact with eachother even to the point of passing directly through each other without colliding.

www.universetoday.com...

Here is an interesting story talking about a Dark Matter Galaxy.

Yarium what's you dicipline? You don't sound like no Layman

[edit on 25-12-2005 by sardion2000]

Actually Sardion, those Ghost Particles are WIMPs! Ghost Particles is another name for them. Basically, they have mass, but they almost never interact with regular matter (such as neutrinos).

As for my discipline, would you believe it, Political Science

But I have a big passion for cosmology and astrophysics - so when I was younger I tried to keep as up to date as possible

I forget the exact numbers, but 95percent or so of all normal matter is space. Nothing. (with the exception of dark matter/energy if it turns out true)

Black holes are not holes they are not gateways. They are simply matter that has collapsed on itself due to gravity finally overcoming the forces holding it apart. (I.E. Imagine the protons, nuetrons, electrons of each atom touching each other. Then every other atom touching the next with no space between)

Eventually (more years then we could probably count) our whole galaxy will end up in the "black hole" at the center. Its gravity does affect us and does overtime slowly pull us towards it.

Our own orbit with the sun will eventually degrade simply because all objects do pull on each other by gravity no matter how far away and no matter how small or immeasurable.
-------------------------------------------

Many scientists now find it hard to reconcile the above with the fact that our universe is currently expanding, and the theory of the big bang. Everyone says after a explosion thing should slow down. In the end though that also is quite easy.

The thing is we are still IN that explosion (implosion).

Anyway.. take a rubber band stretch it taught then let go. It doesnt instantly accelerate to full speed it takes a little bit of time. Once at full speed it doesnt instantly decelerate it takes time.

What I am saying is that after 13+billion years we are still in the beginning phases of that one implosion.