Strange star stumps astronomers

May 16, 2008
The Arecibo Telescope
The Arecibo telescope (aerial view). Photo courtesy of the NAIC - Arecibo Observatory, a facility of the NSF

An obese oddball of a star has left astronomers wondering how it could have formed. Dr David Champion and his colleagues at CSIRO’s Australia Telescope National Facility publish their findings about the star today in the online journal, Science Express.

Found with the Arecibo radio telescope in Puerto Rico, the star is a pulsar – a compact, rapidly spinning star – called J1903+0327. It lies 20,000 light-years away spinning at a rate of 465 revolutions per second – the fifth fastest-spinning pulsar known in our Galaxy.

Astronomers believe such super-fast pulsars started life as the more common, sedate pulsars that spin only a few times a second, but were later ’reborn‘ in their present hyperactive state. This re-birthing or recycling can take place, astronomers think, if the pulsar has a nearby companion that it orbits. At a certain point in its life cycle, the companion pours its own matter onto the pulsar and this extra material ‘spins-up‘ the pulsar.

The process makes the pulsar’s orbit around its companion almost completely circular. Or as astronomers say, the orbit has “low eccentricity”.

“This low eccentricity is one of the best pieces of evidence we have for recycling theory,” Dr Champion says. “But J1903+0327is totally different in that it has a very eccentric orbit which is elliptical rather than circular. So, the question is: How could it have formed?”

The astronomers think the pulsar may once have been part of a triple system of stars and was ’spun-up‘ by its closest companion star – which was either ejected from the system or worn away after it transferred all its mass to the pulsar – and now remains in an elongated orbit around the third, more distant member of the original trio.

But another possible explanation for the pulsar’s odd combination of properties is that it was born in a dense region of stars called a globular cluster, and spun-up by its original partner.

As well as having a highly eccentric orbit, the pulsar is heavier than normal with a mass of about 1.74 times that of the Sun. “A pulsar this massive could also rule out some theories about the state of the highly compressed matter in pulsars,” Dr Champion says.

“Pulsars like this are why you do these surveys,” Dr Champion says. “You don’t want to just find hundreds of objects, you want to find the two or three that are plain weird and we’ve found one.”

Source: CSIRO Australia

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joefarah
4.8 / 5 (6) May 16, 2008
Now the article doesn't say this, but the radius of the star must be less than 100km. Otherwise points on it's equitorial circumference would be travelling faster than the speed of light. That makes its radius 1/7000th that of the Sun, and it's density 600 billion times as dense as the Sun!!! Definitely a neutron star.
soundhertz
3.7 / 5 (3) May 16, 2008
Thanks for that info; I was wondering that too. So that implies that in this process, to satisfy c, the star must always increase density rather than slow down?
1bigschwantz
1.5 / 5 (2) May 16, 2008
At 600 billion solar density, would it not become a black hole?
Lord_jag
1 / 5 (3) May 16, 2008
No it can't be a black hole. It is sending out pulses of energy. That's why they call it a pulsar and not a black hole ;)

Interestingly, I wonder if there is one egection point for energy or many. I have heard of a theory of a egecting from axial points, but I wonder if there might me thousands or millions of ejection points and a slow rate of spin.
Star_Gazer
3.5 / 5 (2) May 16, 2008
Well heres another point.. the mass increases with speed.. right? so if the outer shell of the star, that spins almost the speed of light, becomes very heavy not due to the density, but because its spinning so fast! and I wonder what shape that star is, if its spinning that fast.. I think it would be so facinating to see! =)
robbycoats
5 / 5 (5) May 17, 2008
Uh, black holes certainly are proven. In fact, the most fascinating thing was just observed, yes, observed; a super massive balck hole being completely ejected from its parent galaxy. Welcome to the '90's Mr. Smith... I wish I could still say that.
Teonanacatl
1 / 5 (5) May 17, 2008
This is predicted by the Holofractographic Universe theory; http://video.goog...56390335&q=nassim haramein&ei=RiskSIerKpT6iwL26ICVDA
Ras
4.5 / 5 (2) May 17, 2008
It is a little heavier than "normal", in that a lot of neutron stars seem to have masses consistent with just over the Chandrasekhar limit of 1.4 solar masses (the maximum limit for a static white dwarf). The equivalent limit for neutron stars (Oppenheimer-Volkoff limit) is poorly known since the equation of state (the dependence of pressure vs density) of nuclear material isn't really well known, and could be anywhere from 1.8ish to 3ish. Of course, spinning makes a difference as well. In fact the millisecond pulsars probably represent a maximum rotational speed, set not by the speed of light (these guys have radii like 10-15 km), but by the "break up" rotation rate where the outer surface of the star will just fly off, even given the outrageous gravitational forces at the surface.
The shape is almost certainly distorted from a perfect sphere, although by how much I don't know.
davesmith_au
1 / 5 (6) May 17, 2008
"In fact, the most fascinating thing was just observed, yes, observed; a super massive balck hole being completely ejected from its parent galaxy."

ROFLMAO!! Observed??!! Observed??!! Observed my @r$e!!! Have you even seen the kindergarten picture they called an artist's impression of that one? Tell me this. If these things are observed, why do we only have artists impressions of them? Black holes are science fiction - and that's a fact!

Cheers, Dave Smith.
Ras
4 / 5 (2) May 17, 2008
Aw Gee, Dave. You raise some interesting points that would be worth discussing, i.e. why it is that black holes and neutron stars actually are science and not science fiction, but your style sounds to me like you want to actually hear stuff.
earls
1.4 / 5 (5) May 18, 2008
I challenge anyone to provide a scientifically recorded "picture" or "image" of a "black hole."

Google Image searches for "black hole" and "spiral galaxy," and "galaxy" come up empty.

Galaxies because it's a well known "fact" that super massive black holes reside in their centers.

The whole concept just seems too incredulous to me. They're gravitational wild cards.
hungry4info
5 / 5 (6) May 18, 2008
Dave,

First, I excuse your extreme lack of maturity with your responses ("ROFLMAO!! Observed??!! Observed??!! Observed my @r$e!!! Have you even seen the kindergarten picture they called an artist's impression of that one?"), moving on, you asked a valid question, "If these things are observed, why do we only have artists impressions of them?" They are hard to image. Most of the time, we know where it is just by the X-rays it shoots out. This is especially true of situations where a black hole and star orbit each other. Observing the star, we can determine the mass of the black hole, and we can detect X-rays from the system, telling us that matter is being accelerated to close to light speed, a dead give-away for black holes. It's much like the scenario of extrasolar planets. We know Epsilon Eridani b exists, we've detected the effects on the star, used astrometric observations to determine it's true mass, and so on, but it hasn't been imaged. "Black holes are science fiction - and that's a fact!" This is the saddeningly stubborn state that many people attack from. They are unable (as opposed to unwilling) to be shown wrong. Once they make up their mind on something, it's unchangable. They believe they generate truth, that something is fact because they believe it, completely disregarding any possibility that they may be wrong. I assure you, there is STRONG evidence for the existence of black holes:

I present you Cygnus X-1.
This image, http://blackholes...hp?id=13&img=48 , was taken with a gamm-ray telescope. The central white spot is the gamma rays coming from the inner edge of the acretion disk around the black hole. Note that this is in gamma rays, not visible light. This image, first of all, should show why (what you call "Kindergarden") images of black holes are preferred, the real objects are hard to image. (Do they teach kindergardeners photoshop?)

I present you NGC 6240.
This image, http://www.physor...opti.jpg , was taken from Earth with adaptive optics in infrared light from Kepler.

I present you M87
Here, we can see a Hubble image of the centre of M87. http://space.news..._382.jpg , Guess what! It's a black hole. The jet is clearly visible.

I present you [I don't know it's name, haha]
http://www.fanboy...laxy.jpg shows two galaxies, the bottom one's black hole is emitting particles that are hitting the galaxy above (it would be more accurate to say the particles come from around the black hole, not within it).

Many black holes exist within binary star systems, where one black hole eats a star. SIMBAD lists 257 such systems, known as High-mass X-ray binaries (HMXB), the first ten being
GRO J2058 42
V1521 Cyg
GSC 03588-00834
V2175 Cyg
TYC 3973-812-1
2E 2259.0 5836
TYC 4016-883-1
V490 Cep
V669 Cep
4U 2238 60

You can continue to go on believeing that black holes don't exist all you want, there's certainly nothing preventing you from doing so. I will say that they have been observed, measured, and well studied.

Dave, the electric theory of the universe is completely nonsense. For your information, neutron stars are not unproven. They are known to exist. Pulsars are examples of such and there are thousands of known pulsars (they are easily detectable by periodic flashes).

I wish to now bring up the terrifyingly funny irony of a person advocating the electric theory, and believing black holes and neutron stars don't exist, and then calling those of us who can accept reality "So-called intelligent people [that] wander off into Wonderland".

Cheers.
OckhamsRazor
5 / 5 (3) May 19, 2008
I guess one reason there are no actual pictures of black holes is because they're well...black (for lack of a better description, though it's apparently incorrect to really assume so). We can see stars and galaxies from far away because they are emitting light that we can eventually see. Black holes emit NO light, so all we can see of black holes is their impact on the space around them, or the jets they give off. Artists' impressions just give a nice picture of what the thing most likely appears to be if we were looking right at it ourselves. All we have is the data received from various telescopes that have to be translated (long day and I can't think of the right word pertaining to images!!) into images we can see.

Let me put it in terms you might be able to understand, Dave Smith. You can see a light from a distance when it is turned on, but if you were searching a dark hill at night looking for a light that is turned off, does that mean it doesn't exist?

Of course with black holes there are many more factors to consider, but that's a general idea. It would have been much harder for us to detect and prove the existence of black holes if space were a lot darker and we didn't have stars lighting up the place and providing a backdrop the black holes can interact with. Lucky for us, we do have these things, and though it has taken years of fine tuning and study, black holes are just one of many hitherto theories that are able to be proven as fact.

I'm terrible at explaining, but I think those of you a lot more learned on the subject than I can figure out what I'm saying! It's kind of hard to simplify without omitting too much fact, so my apologies for that.

For now, I'm just going to assume that because all I have here is the name Dave Smith to go by and no real pictures or evidence, that you, sir, don't exist.
robf
4.5 / 5 (2) May 19, 2008
'At 600 billion solar density, would it not become a black hole? ' no, it wouldn't. A black hole forms, supposedly, when the Schwarzchild radius is larger than the source of the "mass" , for the sun, this is appx. 2.95km or some such, for earth, about 9-10mm. If earth was compacted to about 9mm, it'd be a small, black hole. [ r(_s) = 2Gm/c^2 ] (_ subscript / ^superscript) r(_s) is the schwarzchild radius; G , grav const.;m, mass of object; c, speed of light; ... so at 1.7x solar mass, it'd need to be about 4-5km in size at that mass to form a black hole. ... As for you Science-Dave, you sure speak a lot without offering argument to contemporary sciences held truths. You say black holes are science fiction, but what is your argument, 'I can't see it, so it must not be real?', We observe plenty about them, they cannot be so 'directly' observed as they usually swallow up any photons that we'd normally use to say, "hey look there's something there!" but hey, a few of those photons do escape the photon sphere, it's not a 100% thing to swallow light, black holes don't exactly suck anything in, while I'm on that. But next, they do one thing we can see, they spew massive amounts of x and gamma rays. We definitely see this. Anyhow, believe what you will, but if you feel the urge to try and dissuade our belief of firmly rooted science, please, by all means offer a valid argument, don't just tout it as science fiction without reason to why.
thales
not rated yet May 19, 2008
Another interesting thing to think about is that with that amount of mass and rotational velocity, it seems likely that there's a certain amount of frame-dragging occurring around the star. Correct me if I'm wrong (of course), but I can imagine it's possible for the surface of the star to meet or even slightly exceed the speed of light relative to us, though not relative to its own local spacetime.
jeffsaunders
not rated yet Jul 25, 2008
thales - Since c is a constant for all observers we better not say that it can be exceeded in any frame of reference until we change the math.

Not that I mind changing the math - but the new math has to be better than the old math before it will fall into common usage.

Lord Jag - Good point about pulsars perhaps having more than one ejection point in the same plain. If the occasional pulsar had double the number of ejection points in a plain relative to the observers on Earth then it would appear to spin at double speed or at least appear to have a faster spin and/or a different period.

I am not against thinking that opposes the norm but making blanket statements saying that black holes do not exits period does seem a tad outrageous.

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