From Yahoo: Scientists confirm massive black hole in the Milky Way - Dallas-Mavs.com Forums

Royalty_Inc · 10-16-2002, 10:26 PM

Arghhhhh!!! We're all going to die! Oh wait...we were going to anyways.

Someone tell me how they get all those great shots of the Milky Way from the outside considering we are in it???

I've looked for the camera/telescope that does that and Radio Shack doesn't carry it.

The Royal One
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Usually Lurkin · 10-17-2002, 08:10 AM

can you post a link to the pics?

Chiwas · 10-17-2002, 09:09 AM

It´s not a good one, but I'll look for more....

Chiwas · 10-17-2002, 09:10 AM

This is with X-Ray...

Chiwas · 10-17-2002, 09:24 AM

This is infrared...

Usually Lurkin · 10-17-2002, 11:09 AM

what are we looking at here, chiwas?

There seems to be lots of black holes in that last one (and a black square, and some black arrows, too.)

Chiwas · 10-17-2002, 11:29 AM

High-speed orbit

Infrared image of the region around the centre of the Milky Way.
Of all the predictions made by Einstein's general theory of relativity, the one that has captured the imagination of scientists and non-scientists most is probably the possible existence of black holes. But the very nature of these holes makes it difficult to get direct, indisputable evidence that they exist. Despite this, the development of ever more powerful instruments for probing deep into the structure of the Universe has generated a great deal of evidence supporting Einstein's prediction. In this week's Nature, Rainer Schödel and colleagues present perhaps the most compelling evidence yet that a supermassive black hole is present in our own backyard — at the centre of the Milky Way.

Astronomers believe that most galaxies have a black hole at their centre. But the high number of stellar objects at these locations makes it difficult to resolve the motion of individual stars. This means it is hard to pinpoint the position of dark but massive objects, such as black holes. So astronomers have been unable to rule out other explanations, such as the presence of a dense cluster of neutron stars, for the observed motion of stars near a supposed black hole.

Recent improvements in ground-based astronomical imaging techniques — such as 'adaptive optics', which greatly reduces the image-distorting influence of Earth's atmosphere — have given astronomers unprecedented resolving power, even when tracking stars in regions of high stellar concentration. Using such techniques, Schödel et al. conducted a ten-year infrared imaging study of the stars at the centre of the Milky Way, in the vicinity of Sagittarius A* (Sgr A*) — a compact radio source suspected to be a massive black hole. By tracing the orbit of one particular star, they believe that they now have conclusive proof that a supermassive black hole centred on Sgr A* exists.

The star that they tracked orbits Sgr A* in just 15.2 years (for comparison our own Sun takes 230 million years to complete one orbit around the galaxy). At its closest approach, just 17 light hours from Sgr A*, it reaches speeds of up to 5,000 kilometres per second. From the data collected, the authors were able to rule out all other possibilities, and to infer that the star's orbit is caused by the gravitational influence of a central point-like mass of (3.7 ± 1.5) x 106 solar masses — a supermassive black hole.

With continued improvements to the resolution and sensitivity of ground-based telescopes, the authors hope eventually to be able to track the orbits of fainter stars with tighter orbits around this and similar black holes, with the ultimate goal to test still further the predictions of Einstein's theory.

letters to nature
A star in a 15.2-year orbit around the supermassive black hole at the centre of the Milky Way
R. SCHÖDEL, T. OTT, R. GENZEL, R. HOFMANN, M. LEHNERT, A. ECKART, N. MOUAWAD, T. ALEXANDER, M. J. REID, R. LENZEN, M. HARTUNG, F. LACOMBE, D. ROUAN, E. GENDRON, G. ROUSSET, A.-M. LAGRANGE, W. BRANDNER, N. AGEORGES, C. LIDMAN, A. F. M. MOORWOOD, J. SPYROMILIO, N. HUBIN & K. M. MENTEN
Many galaxies are thought to have supermassive black holes at their centres—more than a million times the mass of the Sun. Measurements of stellar velocities and the discovery of variable X-ray emission have provided strong evidence in favour of such a black hole at the centre of the Milky Way, but have hitherto been unable to rule out conclusively the presence of alternative concentrations of mass. Here we report ten years of high-resolution astrometric imaging that allows us to trace two-thirds of the orbit of the star currently closest to the compact radio source (and massive black-hole candidate) Sagittarius A*. The observations, which include both pericentre and apocentre passages, show that the star is on a bound, highly elliptical keplerian orbit around Sgr A*, with an orbital period of 15.2 years and a pericentre distance of only 17 light hours. The orbit with the best fit to the observations requires a central point mass of (3.7 ± 1.5) x 106 solar masses. The data no longer allow for a central mass composed of a dense cluster of dark stellar objects or a ball of massive, degenerate fermions.
Nature 419, 694–696 (17 October 2002)

nowitzki_prophecy · 10-17-2002, 12:06 PM

there are thories that there is a massive black hole in almost every galaxy,not only that,it says the galaxy is depended on the black hole.
i could explain it much better but it would take some time,if anyone want me to pm me.

Chiwas · 10-17-2002, 12:24 PM

The two arrows point to the position of the black hole.

(Go ahead, N-P, I like to read science)

MavKikiNYC · 10-17-2002, 12:56 PM

And I thought this was going to be some joke about Oliver Miller and a candy bar...

nowitzki_prophecy · 10-17-2002, 01:06 PM

o.k forgive me up ahead if i say some stuff wrong but its very hard to talk scientific stuff in a different languege.

well,acording to what i remember,everything starts with alot of dust(dont know how its said in english,its like stardust),the black hole swirel the dust,and pulling it at the same time,some of the dust is dragged by the hole,some is pusshed back by the spinning dust,the spinning dust touches itslef in an incredible speed,and so it glows,(heat=light),the hole pulles the dust inside,(there are several black holes thoerys,one of my favorite is:a great plannet in the size of adlist the sun,go through several stages,theres the giant red,than the giand blue,than the tiny white,tiny white is when the plannet is consumed by his energy,his entire matter is been shrinked to a plannet the size of a medium city,a head of a pen made by that matterial weighs as much as the empire state building,so,acording to what albert einstein proved,light is pulled by gravity like any other thing,so,this white dwarf thingi plannets gravity is so strong that light is pulled to it and doesnt get back out,it cant bounce of the plannet,so you cant see it,thats black hole!)so the dust that is cercuil(like a 0),and thats the black holes you can see,its the dust that glows around them,when the black hole consume the dust that was around him,thats when its getting very hard to ditact.
everything around us changes space,the black hole rippes it,so,the time is toren,time is slowed when you go near a black hole and when you reach the middle,it stopps,the middle is caled the singularity,its the most not undderstood thing there is,we know nothing about it,nothing,people think that over there all physics laws stop exziting.
well,i can go on like this for a long time so i'll just stop,hope you didnt fell asleep,remember,you asked for it.

Usually Lurkin · 10-17-2002, 01:30 PM

thanks, n_p.

sounds very much like nellie's doghouse.

Great news about the time stopage thing! If Bradley makes it all the way out, maybe he'll be playing like it's still 00/01.

Chiwas · 10-17-2002, 02:15 PM

Stephen Hawking says that black holes irradiates x-ray: when an electron reachs the singular horizont, produces an anti-electron (positron), then both eliminates each other producing a x-ray photon which escapes away the black hole.

(forget the grammar)

nowitzki_prophecy · 10-17-2002, 03:42 PM

i dont know even if an x-ray photon can escape a black hole,and what do you mean about the anti matter causes explosion,you cant get the matter and the anti matter at the same place without some sort of chemical reaction.

nowitzki_prophecy · 10-17-2002, 03:47 PM

of course there are these thoeries about every black hole being a wrom hole to somewhere else in the universe,though it sounds cool,i really dont believe.
what do you know about travel mate?thats interestin shit.
you see,acording to my friend albert,nothing can pass the speed of light,cause your weight would be endless,so,again there are thories,what about if you could pass into other dimention,there you could pass the speed of light and jump back to your dimention,snappy shit.

nowitzki_prophecy · 10-17-2002, 03:53 PM

plus,with all the respect to stephen,who is the smartest man today,he couldnt have the first idea what happens in the singularity.

Drbio · 10-17-2002, 04:02 PM

Well, I am most definitely not going to post it here, but I went to google.com and typed in Milky Way Black Hole and one of the links had nothing to do with astronomy I can assure you.

Good Lord.

nowitzki_prophecy · 10-17-2002, 04:06 PM

hahahahaha

Chiwas · 10-17-2002, 04:29 PM

N-P: Stephen makes equations. He is the only one who can understand them because he employs a cipher and the Esc key when somebody approaches.

There are no chemical reactions, they call it "quantum jump".

Maybe is the kind of jumping needed to crash Shaquille's toe.

Chiwas · 10-18-2002, 09:28 AM

"SAGITTARIUS A-STAR is invisible to the naked eye but when viewed through a radio telescope appears so bright that many believe only a black hole's gravity could fuel it." Scientific American.

nowitzki_prophecy · 10-18-2002, 02:41 PM

amazing,simply amazing.

Royalty_Inc · 10-19-2002, 03:59 PM

I hope you guys are getting paid for all that you know...I bow down to you.

TRO

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Chiwas · 10-19-2002, 09:53 PM

It's better had it as a hobby.

If it was a job, I'd hate it.

[img]i/expressions/face-icon-small-wink.gif[/img]

nowitzki_prophecy · 10-21-2002, 02:08 PM

yea,you dont want to have deadlines and pressure on stuff like that,it would just make you hate what you love...

Chiwas · 10-21-2002, 07:08 PM

This is my favorite. It's a picture composition of some piece of the Universe.

Each little dot is a <u>Galaxy</u>!!

nowitzki_prophecy · 10-22-2002, 06:03 AM

again,simply amazing.
hey chiwas,you need the thoery about the universe recicling itself?
i heard that the universe is now sherinking,people believe its because te gravetys of the plannets is too strong and he's shrinking,until he'll be so small he'll explode,a big bang,than the universe will start again,and you would be the same,we would have the same conversation after about 6 billion years,until it happens again...
cool hua?

Usually Lurkin · 10-22-2002, 07:22 AM

<< again,simply amazing.
hey chiwas,you need the thoery about the universe recicling itself?
i heard that the universe is now sherinking,people believe its because te gravetys of the plannets is too strong and he's shrinking,until he'll be so small he'll explode,a big bang,than the universe will start again,and you would be the same,we would have the same conversation after about 6 billion years,until it happens again...
cool hua? >>

so are we having this conversation backwards right now, as the universe reverses in on itself?

Chiwas · 10-22-2002, 07:45 AM

I have read some about it. It's called "Big Crunch", but you are better to explain it, N-P. If you do that, I can add some little details if needed.

The backwards conversation -backwards life, you born old and dies baby, and walks backwards too- is linked for some scientifics to the theory but they couldn't probe it in laboratory yet.

Some say there is not enough matter to let the universe colapses itself by gravity, and others have invented the "dark matter" to justify the theory.

I wonder if it happens and we could talk again this conversation, if we'll can remember it. "Hey N-P & U-L, what's up? talk about recicling universes again?"

Well, N-P, you can start the symphony.

nowitzki_prophecy · 10-22-2002, 09:34 AM

haha,start the symphony,i like that...
o.k,i pretty much said most of what i know about that but i could try and elaborate.
as i said,its pretty simple despite the mass and size of the universe,the univerese is being pulled inwards by the gravity of the galaxys,we are now in the process of shrinking,but it doesnt mean everything is backwords,the fact that space is getting smaller doesnt change how time works,you would live as you lived before,what i ment was that in a couple of bilions years the big beng will happen again and so does the recreation of galaxys and planets,and acording to the chause(didnt writen it right) thoery everything should be the same cuase there isnt any other element to affect it,so in time yes we would have this conversation again,if you think of it,we already had,so,oh so many times... [img]i/expressions/face-icon-small-smile.gif[/img] i wonder how many rings the mavs got...
i remember a few things about dark matter,one thing is its very very very hard to find,its kinda similr to a "white dwarf" plannet,you cant see it,light cant escape it,so one way to catch it is to take endless photographs of different places and compare them to photographes you take 6 monthes later,if you see a new plannet,it probably means you got yourself some dark matter,it was in the way of seeing the other plannet so you just saw space.
i remember earing that dark matter is involved in the explosion of an atom bomb,i dont remember exactly what it was,but something like dark matter is formed and released in the explosion of an A bomb,something like that.
hope you'll enjoyed... [img]i/expressions/face-icon-small-smile.gif[/img]

Chiwas · 10-23-2002, 06:40 PM

An article from science News.

Lonely Universe
Runaway expansion will lead to dark times ahead
Ron Cowen

Early in 1998, our perception of the universe got a jolt. Two independent teams of researchers studying distant supernovas found evidence that the cosmos is doing more than merely expanding. The teams discovered that it is expanding at an ever-faster rate (SN: 4/7/01, p. 218: http://www.sciencenews.org/20010407/bob14.asp). Opposing the tug of gravity, there seems to be some mysterious force, dubbed dark energy, that stretches space-time and pushes galaxies apart.

UNRAVELING WEB. Distribution of dark matter and galaxies, from left to right, 3 billion years after the Big Bang, today, and 50 billion years in the future. Galaxies that haven't already begun gathering together will be unable to do so in the future.
Busha, R. Wechsler, F. Adams, Evrard/U. Michigan

Although the evidence is still under debate, scientists are beginning to explore the full consequences of living in a revved-up universe. And as several cosmologists have come to realize, antigravity has a downside.

Because gravitational attraction was dominant when the universe was younger and objects were closer together, runaway expansion didn't begin until about 5 billion years ago. But to those who are superlatively farsighted, this relatively new trait of the universe couldn't have more profound consequences.

That's the thought that came to Harvard cosmologist Avi Loeb one morning last year, after being kept awake most of the night by his own personal reminder of the future, his 1-month-old daughter. Loeb realized that in a revved-up universe, galaxies eventually would recede from each other at faster than the speed of light. Although the laws of physics hold that nothing can move faster than light in any local region of the universe, two widely separated galaxies, pushed apart by the expansion of space-time between them, can have a relative velocity that exceeds the local limit.

When that happens, all possibility of communication between those galaxies, or even visual contact between them, dies. At that point, light emitted by one of the galaxies will never ever catch up to the other.

Rather than seeing the opposite galaxy vanish from sight immediately, an observer in one galaxy will see the light from the other gradually grow dimmer like a dying ember (see below). Ultimately, the remote galaxy will become so dim that not even the most sensitive telescope will be able to detect it. In the end, evidence of all but the nearest galaxies will become forever inaccessible.

If would-be stargazers in the Milky Way were to be observing the universe billions of years from now, they would see a dark and desolate canvas, says Loeb. Our galaxy's closest neighbors, those whose gravitational attraction had managed to resist the repulsive force of dark energy, already would have merged with our own into a new supergalaxy. As for the other 50 billion galaxies in the universe, none would be visible. The supergalaxy would appear as an island unto itself, note Loeb and his Harvard colleague Kentaro Nagamine in an article they recent posted on the Internet.

As the future of the Mavericks trades, the future of the Universe is also plenty of alternatives; each of them very attractive and speculative.

nowitzki_prophecy · 10-24-2002, 09:25 AM

good show chiwas,but i tend to believe on the thory i mentioned earlier,about the universe expendind and shrinking all the time,it sorta explains what was before the big bang,it explains what was since the beggining of time,but i was wrong when i said the univerese is shrinking,my physics teacher told me that aswell,i guess i got confused.
can you explain something to me?if the galaxys are driffting apart in a speed faster than the speed of light it only makes tham invisble from one galaxy to another,not from the rest of the universe,so the universe wouldnt be a dark and desolate canvas.
maybe i misinterproted.

Chiwas · 10-24-2002, 10:06 AM

You´re right, but we have to remember that they are only theories; they are not proved. There are many of them, and each has his own details.

For example, many scientists don't believe that any thing in the universe could travel faster than light, in accord with Einstein's Relativity Theory.

Others think that before some galaxy can reach this speed, the universe will be a dark and almost empty space and very huge. No more energy and no more light, only death matter.

Others think that the Dark Matter is big enough in order to begin the Universe shrinking and finally ending in the Big Crunch. And could be (another theory), starting a new Universe.

But supposing that the theory of the last article was true, and the galaxies could travel faster than light, yes, they would be only invisible to us and not for the universe; for example, if two galaxies were neighbors and both of them'd travel faster than light, they could see each other. But i'd be a very crazy universe. One of the writers said "...I find it very disturbing because it is so bleak".

One funny cartoon for relaxing the concentration:

Usually Lurkin · 10-24-2002, 11:08 AM

we are now in the process of shrinking,but it doesnt mean everything is backwords,the fact that space is getting smaller doesnt change how time works,you would live as you lived before,

well, crap. I was already saving up money to place a bet on last year's superbowl. (or was I spending it? [img]i/expressions/face-icon-small-confused.gif[/img] )

Didn't Einstein say that there is some sort of relationship between amount of matter and speed of matter, or something? So that the faster something goes, the bigger (but less dense?)it is? Or the more massive (more gravity) the faster?

I guess I'm asking if the nature of gravity will change in any of the theories.

nowitzki_prophecy · 10-24-2002, 02:45 PM

yea,from what i know the dencer the same body is,the stronger his gravity is.
its like i said earlier,with the "white dwarf",its se denced that light cant escape it cause the gravity is too strong.

Chiwas · 10-25-2002, 06:38 PM

Astronomer sees black hole eat star
Thursday, October 24, 2002 Posted: 10:12 AM EDT (1412 GMT)

Drawing of black hole

WASHINGTON (Reuters) -- It began like a routine measurement on a quasar, a somewhat boring look at the emissions from a distant, early galaxy -- but it turned out that the graduate student was actually watching a black hole swallow part of a star.

As he looked at the spectrum of light sent out by TEX 1726+344, the student at the University of Texas at Austin, Feng Ma, realized he was seeing something extraordinary.

It looked like the quasar was ejecting a cloud of matter at a speed of 3,700 miles per second (6,000 kms per second), Ma said in a statement. "This leads me to think it's the signature of a star that's been ripped apart by the black hole's gravity."

"Half of the star's matter fell into the black hole, and the other half was ejected in a gravitational sling-shot."

Quasars are bright smears of light so distant in space and time that astronomers think they are early galaxies formed when the universe, which is expanding, was young.

They are believed to have black holes at their centers. Black holes are objects so dense that they suck in just about everything around them with their huge gravitational fields.

But usually their "victims" are ripped apart in the process, ejecting part of their matter at high speeds that create radiation that can be seen from the distant Earth.

Or at least theoretically, that is what happens. Usually astronomers have just circumstantial evidence of this, in the form of leftover stardust circling the black hole.

Ma believes he may have seen the black hole in action.

He said if the spectral measurement changes in several years, this will help prove his theory.

"If this interpretation is correct, we could see this feature in the spectrum go away in the next few years. I'd like to keep an eye on this quasar to see what happens," said Ma, who reported his findings in the Monthly Notices of the Royal Astronomical Society.

<< the student at the University of Texas at Austin, Feng Ma >>

Some D-M.com friends from Austin can be proud of this [img]i/expressions/face-icon-small-wink.gif[/img]

nowitzki_prophecy · 10-26-2002, 07:16 AM

where do you get this stuff?this is great,beautiful picture

Chiwas · 10-26-2002, 10:33 AM

CNN.com in Science & Space, in NEWS.

Link

Chiwas · 10-26-2002, 11:01 AM

Did Newton Get It Wrong?
Evgeny Podkletnov's antigravity technology may sound far-fetched, but it's attracting serious interest from the likes of NASA and Boeing.
By Matthew Maier, October 2002 Issue

Russian scientist Evgeny Podkletnov is challenging one of the most sacred tenets of physics -- the law of gravity. Podkletnov claims that when objects are placed above a high-temperature, superconducting ceramic disk rotating within an electromagnetic field, the objects lose as much as 2 percent of their original weight. He calls the effect "gravity shielding," and when word of his research reached the public in 1996, a brief media circus ensued. Many in the physics community dismissed his effort as wishful thinking.

Now, however, several mainstream organizations -- including Boeing (BA), NASA, and British aerospace giant BAE Systems (BAESY) -- are lending fresh credibility to Podkletnov's claims. Phantom Works, Boeing's top-secret R&D arm, recently disclosed that it is monitoring his research. "We've seen his work, and we'd like to see it developed further," says Boeing spokesman Dave Phillips. Meanwhile, NASA's Marshall Space Flight Center has awarded a $600,000 contract to Ohio-based Superconductive Components in an attempt to build its own version of Podkletnov's gravity-shielding device -- the effort should be complete later this year.

So far, other scientists have been unable to duplicate Podkletnov's results. But the appeal of such a device remains irresistible. Applications may include space transportation (for rocketless propulsion), missile defense (to alter the trajectory of incoming threats), or even gravity-beam weapons (pulverizing objects by subjecting them to massive G forces). "Clearly, we don't know all there is to know about gravity," says NASA project manager Ron Koczor. "But I have a gut sense the shielding effect could be real." If so, gravity could one day become an even greater force to be reckoned with.

Chiwas · 10-26-2002, 08:25 PM

A flower in the Universe

The Cocoon Nebula

irontoad · 10-28-2002, 02:34 PM

Hey Chiwas, I've got a question for you, I've been reading stuff about theories of the universe, and something I can't grasp is the concept of time dilation. How does any type of clock (digital, mechanical) slow down the faster it approaches the speed of light? Thanks if you can give me any input.

Also, along with the theme of this thread, if you've never heard of him, look up John Hutchison or 'the poltergeist machine' in an internet search engine. It's some really interesting stuff regarding physics.