A dust factory around a dead star

Feb 24, 2009
An image of the sub-mm radiation emission from dust in and around Cassiopeia A. The overlaid black lines indicate the polarised signal from the dust within Cassiopeia A, with the strength marked by the length of each line. The scale bar represents 30% polarised emission. The direction of the lines indicates the orientation of the magnetic field in Cassiopeia A. Image: Loretta Dunne, University of Nottingham.

(PhysOrg.com) -- A team of astronomers, led by Loretta Dunne from the University of Nottingham, have found some very unusual stardust. In a paper to be published in Monthly Notices of the Royal Astronomical Society, Dr Dunne and her team find new evidence for the production of copious quantities of dust in the Cassiopeia A supernova remnant, the remains of a star that exploded about 300 years ago.

Interstellar dust is found throughout the cosmos. It is responsible for the dark patches seen in the Milky Way on a moonless night. It consists of carbon and silicate particles, about the size of those in cigarette smoke. The dust helps stars like the Sun to form and subsequently coagulates to form planets like Earth, and the cores of giant gas planets like Jupiter. It is found in great quantities in galaxies, even very early in the history of the Universe.

The origin of all this dust is, however, a mystery. Does it condense like snowflakes in the winds of red giant stars or is it produced in supernovae -the violent death-throes of massive stars? Supernovae are a good way to produce dust in a blink of the cosmic eye, as massive stars evolve relatively quickly, taking a few million years to reach their supernova stage. In contrast lower-mass stars like our Sun take billions of years to reach their dust-forming red giant phase. Despite many decades of research, astronomers have still not found conclusive evidence that supernovae can produce dust in the quantities required to account for the dust they see in the early Universe.

A multi-colour image of the Cassiopeia A supernova remnant. The overlaid lines indicate the polarised signal from cold dust within the remnant with the strength marked by the length of each line. The temperature of this dust is around -250°C. The scale bar represents 30% polarised emission. The direction of the lines indicates the orientation of the magnetic field in Cassiopeia A. The underlying image is a composite of data from the Chandra X-ray observatory, the Hubble Space Telescope and the Spitzer Space Telescope. The red colours are infrared light from hot dust at 10°C, yellow is optical light from gas at 10,000°C and the blue/green colours show X-rays from gas at 10 million °C. Image credit: Submm:Loretta Dunne, University of Nottingham; X-ray: NASA/CXC/SAO; Optical: NASA/STScI; Infrared: NASA/JPL-Caltech.

Using the SCUBA polarimeter on the James Clerk Maxwell Telescope in Hawaii, the scientists searched for a signal from dust grains spinning in the strong magnetic field of the supernova remnant. If the dust grains are slightly elongated (like little cigars) they tend to line up the same way and produce a polarised signal. When the polarimeter detector is rotated, the strength of the signal changes - much the same as if you look at the sky with polaroid sunglasses held at different angles.

The polarisation signal from the supernova dust is the strongest ever measured, anywhere in the Milky Way, so the supernova dust must be quite unusual. It emits more radiation per gram than regular interstellar dust and the alignment of the grains must be very orderly to produce such highly polarised emission. “It is like nothing we’ve ever seen” said Dr Dunne. “It could be that the extreme conditions inside the supernova remnant are responsible for the strong polarised signal, or it could be that the dust grains themselves are highly unusual”

Team member Professor Rob Ivison of the Science and Technology Facilities Council’s Astronomy Technology Centre in Edinburgh comments further. “It could be that the material we're seeing is in the form of iron needles - exotic, slender, metallic whiskers. If these grains are distributed throughout the Universe they may be re-radiating microwaves. This has major consequences for our understanding of the cosmic microwave background - one of the most important building blocks of the Big Bang model of our Universe”.

Alternatively, the grains could be a more pristine version of the dust found elsewhere in the Galaxy, with the same composition but able to produce more radiation due to the nuances of its 3-D structure. A final verdict requires further observations using the Herschel Space Observatory, set to be launched by the European Space Agency in April.

More information: L. Dunne, S. J. Maddox, L. Rudnick, T. A. Delaney, B. C. Matthews, C. M. Crowe, H. L. Gomez, S. A. Eales and S. Dye, "Cassiopeia A: dust factory revealed by submillimetre polarimetry", Monthly Notices of the Royal Astronomical Society, in press.

Provided by Royal Astronomical Society

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User comments : 8

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yep
1 / 5 (4) Feb 25, 2009
Cool Pictures of a supernova Proving they are "Catastrophic electrical discharges focused on a star"
http://www.holosc...re6qxnz1
Ethelred
5 / 5 (2) Feb 25, 2009
Proving no such thing. Its truly amazing the nonsense you spout. You and Alexa should get together for for a gathering of cranks. The torque could change the Earth's rotation.

Ethelred
yep
1 / 5 (3) Feb 26, 2009
Not the dust, pictures on this cool site.
http://www.holosc...re6qxnz1
Ethelred
5 / 5 (2) Feb 26, 2009
There is no such thing as a cool crank site.

Simply claiming a super nova is the result of some bizzare and totally imaginary Electro Blasto in no way proves you aren't a crank. Pretty much confirms it.

By the way, you are boring. ALEXA is much more entertaining.

Ethelred
yep
1 / 5 (4) Feb 27, 2009
After learning about plasma science, I would be a crank if I still believed in Quantum theory.
Maybe your bored because you already know everything, or maybe your just old and set in your beliefs. There was a great article on how older people told a lie several times will still believe in the lie even if told the truth.
Ethelred
4.7 / 5 (3) Feb 27, 2009
After learning about plasma science, I would be a crank if I still believed in Quantum theory.


Since Quantum theory works and the computer you use is dependent on quantum effects and not plasma(assuming you have an LCD monitor)then denying the Standard Model does indeed qualify you as a crank.

Maybe your bored because you already know everything


I don't have the delusion that I know everything. You however have made it clear that you have the ANSWER to everything. I guess I should worship at your feet. May I wash them oh wise and noble sensai.

or maybe your just old


Depends on your definition of old. You seem to have a know a it all prejudice there. Is that AWITBS theory or Plasma Theology?

set in your beliefs.


Keep your mind open, but not so far open your brains fall out. You should pick yours up before you step on it.

There was a great article on how older people told a lie several times will still believe in the lie even if told the truth.


I guess you must be about a million years old then. And not learned a thing since you heard about the forth state of matter. Bad research you have there. College students have the same trouble. Just try talking about evolution with them. Amazing how many think the world is young.

When you stop learning or playing you are a dead man walking.

Don't try that ad homonym crapola with me. Humor will beat it every time. Even better than experience sometimes.

Ethelred
yep
1 / 5 (3) Mar 01, 2009
How is an electric blasto any more bizarre or imaginary than back holes or dark matter?
And have you done any reading on plasma cosmology?
Here is a good start.
http://www.electr...xOLD.htm]http://www.electr...xOLD.htm[/url]
This is also a great link.
http://www.electr...xOLD.htm]http://www.electr...xOLD.htm[/url]
I hope my avidya does not deter you.
Ethelred
5 / 5 (2) Mar 02, 2009
How is an electric blasto any more bizarre or imaginary than back holes or dark matter?


Total lack of evidence. Total lack of any numbers to show HOW it could cause a star to blow up.

There is evidence for black holes. There is evidence for dark matter and your claims about plasmas did not produce anything that would match the rotation rates of galaxies.

And have you done any reading on plasma cosmology?


Yes I followed your links the first time I saw them. I didn't see anything convincing. Especially in regards to supernova where the physics has been checked to a high level of confidence, at least for most cases. Its NOT a bounce on matter that drives the expansion in large Supernova. Its neutrino pressure on matter so compressed that even neutrinos at the density involved in a an Iron collapse cannot pass through without imparting momentum to the falling outer shell of the dying star.

Please keep in mind that a neutrino pulse was detected shortly after the light was first seen. One of the detectors detected a pulse significantly later than the other. It was not designed to detect electron neutrinos like the others and thus the set of data was the first real evidence that not only did neutrinos have mass there had to be at least two different masses involved thus making a flavor change possible.

Your links are broken. However as a skilled Web Warrior and brilliant abuser of Google I managed to figure out that it the same site you usually post. I will give it another look.

Electrodynamic forces in electric plasmas are much stronger than the gravitational force.


Within the plasma. Not outside it. So it has no long range effect. Ions have both positive and negative charges so over fairly short distances the two fields will begin to overlap and then cancel. This is unavoidable. In the lab we can separate the electrons and protons by expending quite a bit of energy. In space this sort of thing is just a tad hard to maintain.

Mainstream astrophysicists are continually %u201Csurprised%u201D by new data sent back by space probes and orbiting telescopes. That ought to be a clue that something is wrong.


What a ridiculous statement. What it proves is that the probes were sent to the right places to learn things we didn't all ready know. That is what they are for.

New information always sends theoretical astrophysicists "back to the drawing board".


That sounds very much like a Creationist talking about fossils. Fossils that usually show that the Creationist is wrong no matter what the scientists later learn. The whole idea is to learn. Where is YOUR prediction that the probe would find what was found? I notice a lot of handwaving in front of the EC drawing board to explain stuff that WASN'T predicted by EC either.

Astrophysicists and astronomers do not study experimental plasma dynamics in graduate school.


Electrical engineers do not study gravity. They don't learn tensor calculus so they don't have the tools to make claims about gravity. Let me know when Dr. Scott learns the General Theory of Relativity so the he can make VALID claims as to which is right.

pseudo-scientific invisible entities such as neutron stars


So non-visible that they show up in x-ray and gamma ray telescopes, have detectable accretion disks, rip matter from visible stars and in at least one case an orbiting pair has decay that matches gravity wave theory.

http://www.atnf.c..._binary/

http://arxiv.org/.../0407149

So not only do neutron stars exist, pairs behave according to the General Theory of Relativity. Thus its a REAL theory and not some WAG that is being called one. Unlike your EC stuff or the String Hypothesis for that matter. At least String fans have some functioning math.

When confronted by solid evidence such as Halton Arp's photographs that contradict the Big Bang Theory, their response is to refuse him access to any major telescope in the U.S.


When confronted with the COBE evidence EC fans pretend they didn't hear.

Instead of wasting time in a futile battle trying to convince entrenched mainstream astronomers to seriously investigate the Electric/Plasma Universe ideas, a growing band of plasma scientists and engineers are simply bypassing them.


I heard that same kind of bilge at a quack convention on The Miracle Mile. Named after all the quacks that conned the desperate there.

Einstein didn't have to bypass. He just confronted the establishment with well written papers that actually had solid work done on them.

This web site is dedicated to explaining the basis of this ongoing scientific shift


You know making claims of a shift when there is pretty much no one working in the field on your side is a standard in politics. Its an attempt to create a Band Wagon out of nothing and hoping for leverage. It does work sometimes in politics but there people can't always check the man behind the curtain.

If the Sun is essentially an electrical phenomenon, as seems to be the case, and it is also a fairly typical star, then all stars should exhibit properties that are consistent with the Electric Sun (ES) model.


Make an assumption then go on as if it was true. Not actually a bad way to do things. As long as you keep it mind that it IS an assumption and you have to be careful to avoid circular reasoning. Its amazing how hard it is to point out circular reasoning to Fundamentalists for instance.

It is clear that the HR diagram is a plot of actual observations %u2013 not something deduced from theory.


Hey actual use of data.

Is the Electric Sun (ES) model of how a star is powered consistent with the HR diagram? If it is not, then this would disprove the ES hypothesis.


True but it wouldn't disprove the standard model as that DOES fit the evidence.

The absolute luminosity of a star, therefore, depends on two main variables: current density at its effective surface, and its size (the star's diameter).


Only if the temperature is caused by this alleged current flow and not from heat from below. Interestingly enough sunspots, that are the one area of the Sun where we do know there is current flow, have LOWER temperatures then the rest of the Sun. This is counter to your theory. Thus it is wrong.

EC loses to gravity. But I will cover more as the bull gets deeper in short order. I may need a snorkel if I go on too long.

If all stars are indeed powered by a nuclear fusion reaction as is claimed, with the T dwarfs we must be in the 'cold fusion' range!


If you look at the site notice that before that he was engaging in the Circular Reasoning that I predicted. Ethelred's Crank Theory is vindicated again. But in this case he chooses a star that is NOT on the Main Sequence and tries to use Main Sequence theory on it. Not an honest thing to to do unless of course he simply does not have a clue.

Many of the dwarfs do not meet these requirements. One mainstream astrophysicist, realizing this, has said that these dwarfs must be powered by 'gravitational collapse'.


Which is exactly what anyone should expect. Its not on the Main Sequence so it is not going to be burning hydrogen as its main source of energy. In fact at one time in 1800's gravitational collapse was on of the main ideas of where the Sun got its energy. This led to a problem since the numbers worked out to the Sun being younger than the Earth.

A star this cool should not be capable of X-ray flare production.


Only if you ignore the fact that the star could indeed have electrical storms since even Main Sequence stars have them. Plasma effects do not gainsay actual core fusion in Main Sequence stars nor is there any reason to believe that there is no fusion at all in the T stars.

This transition will be accompanied by a rapid change in the voltage rise across the plasma of the star's atmosphere. Maxwell's equations tell us that such a change in voltage can produce a strong dynamic E-field and a strong dynamic magnetic field. If they are strong enough, dynamic EM fields can produce X-rays. Another similar phenomenon can occur if a star makes the transition from normal glow to arc mode.


There is just a small problem there. Where the heck is the energy coming from to drive the current? In standard theory with fusion this is not a problem.

we enter the spectral M range where some arc tufting becomes necessary to sustain the star's electrical discharge.


Also of course a source of energy to drive it is still totally absent.

A more informative way to say this would have been that "Half of this star's surface is covered by photospheric arcing."


Which is the cold part of the star and not the hot part. Which is exactly the opposite of EC Cranking.

That the stars do not all fall precisely on a line, but have some dispersion above and below the line, is due to their variation in size.


Maybe in your crank world. In the world that is predicted by gravity and fusion that is MUCH better explained by the age of the star. Older stars of the same mass are hotter according to the standard theory . This matches the actuall H-R diagram unlike EC Cranking which is claiming its a matter of mass alone. If it WAS a matter of mass than there would NOT be any dispersion. That was hand waving of the worst sort.

As we approach the far upper-left of the HR diagram (region of highest current density), the stars are under extreme electrical stress - too many Amps per sq. meter.


More circular thinking. A sure sign of Cranking.

Even farther out to the upper left is the region of Wolf-Rayet stars. Extreme electrical stress can lead to a such a star's splitting into parts, perhaps explosively. Such explosions are called novae. The splitting process is called fissioning. A characteristic of Wolf-Rayet stars is that they are losing mass rapidly.


I haven't seen that much handwaving since the Rose Parade. There is no splitting process so no one except the author is calling it fissioning. Everyone else calls it a nova. Splitting a star would involve staggering levels of energy and there would no longer be a star. There would be a Super Nova type B for bogus since none exist.

This crap doesn't get any better farther on. Just more handwaving and circular reasoning and of course a total lack of understanding of the standard model.

O.K. its not as deranged as Dr. Brown's Hydroplate Cranking but it is traveling in the same direction. Towards fantasy land. The usual trick of taking quotes out of context and carefully failing to notice that the person quoted has seen it as way to learn new things and not a need a for a radical theory that so far consists of magic thinking as there is no source of energy to drive the claimed currents over billions of years. Without a source of energy that can explain how the Sun has burned as long as we KNOW it has then its not theory, its Cranking.

On a Crank scale of 1 to 10 with Hydroplate coming in at 10 EC is at least a 6 and without a power source that makes sense I have to give it 7. Further exploration could easily move it to 8. For instance any claim that the Earth is much younger than at least 3.8 billion years would move it into YE Creationists classes that have a minimum of 9. A 10 requires exceptional entertainment value akin to Hydroplate.

Ethelred