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Right Before Our Eyes (Pulsar started emitting powerful bursts of x-rays like a magnetar.)
ScienceNOW Daily News ^ | 21 February 2008 | Phil Berardelli

Posted on 02/23/2008 9:05:41 PM PST by neverdem

Enlarge ImagePicture of neutron star

Growing pains.
This artist's conception shows a neutron star known as a magnetar crackling with extremely powerful magnetic activity.

Credit: Gregg Dinderman/Sky & Telescope

"When you hear hoofbeats," the old saying goes, "think horse, not zebra." But what if your horse suddenly grows zebra stripes? That's the predicament astronomers faced when a star they were observing--a rapidly spinning remnant of a supernova called a pulsar--started emitting powerful bursts of x-rays considered the hallmark of a much-rarer object called a magnetar. The finding strongly suggests that pulsars, also known as neutron stars, and magnetars are linked and paves the way for a better understanding of stellar evolution.

Pulsars are the dense cores left over after stars of a certain mass explode into supernovae. Weighing as much or more than the sun but only as big as asteroids, they can rotate tens or even hundreds of times a second (versus once a day for Earth). Sky surveys have identified about 1800 pulsars within the Milky Way, most of which emit pulsing radio signals that rise and fall as the pulsars spin.

The stripe-changing pulsar, named PSR J1846-0258, lies about 20,000 light-years away in the constellation Aquila. A team of researchers from NASA and elsewhere was observing it using the Rossi X-ray Timing Explorer (RXTE) spacecraft when the star suddenly erupted in a blast of x-rays. The display, reported online today in Science, made PSR J1846-0258 a candidate for being a magnetar--a type of neutron star with an enormously powerful magnetic field. Magnetars, so rare that only a dozen or so have been discovered, routinely emit high-energy x-rays and even gamma rays. But no one had ever observed a pulsar emitting such bursts.

"The bursts were completely unexpected," says astrophysicist and lead author Fotis Gavriil of NASA's Goddard Space Flight Center in Greenbelt, Maryland. Because PSR J1846-0258 is a very young pulsar (a mere 1000 years old) and because its magnetic field strength is considerably lower than those from bona fide magnetars, Gavriil says, the researchers suspect it is still evolving. He says the discovery raises important questions about the two types of stars: Do pulsars behave like magnetars only periodically and then revert? Did all magnetars originate as pulsars? "We really need to follow this source, and others like it, to answer these questions," he says.

Astrophysicist Duncan Lorimer of West Virginia University in Morgantown calls the discovery "fantastic." A decade ago, he says, very little was known about any connections between pulsars and magnetars. Now, Lorimer says, the evolutionary connections between the two are strengthening, and observations like this one will help "elucidate our understanding of what happens to a young neutron star after its birth in a supernova." And astrophysicist Robert Duncan of the University of Texas, Austin, calls the findings "fascinating and important," because they represent the first time that magnetically generated x-rays have been seen coming from a rotationally driven pulsar. Duncan, who developed the theoretical behavior of magnetars in 1992, says he is not so sure the object will turn out to be a magnetar, but "neutron stars are constantly surprising scientists, so future observations … will certainly be interesting."

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TOPICS: Culture/Society; Government; News/Current Events
KEYWORDS: astronomy; catastrophism; magnetar; pulsar; xplanets
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To: KevinDavis; annie laurie; garbageseeker; Knitting A Conundrum; Viking2002; Ernest_at_the_Beach; ...
 
X-Planets
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21 posted on 02/24/2008 7:37:28 AM PST by SunkenCiv (https://secure.freerepublic.com/donate/___________________Profile updated Tuesday, February 19, 2008)
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To: grey_whiskers
Kinda hard to fit an entire star into a test tube...

Not if you have a really big test tube!

22 posted on 02/24/2008 8:36:49 AM PST by Eaker (If illegal immigrants were so great for an economy; Mexico would be building a wall to keep them in)
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To: SunkenCiv

Ahhh...my eyes!!


23 posted on 02/24/2008 8:51:23 AM PST by blam (Secure the border and enforce the law)
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To: blam

Aha... finally, retaliation for those Zowie pictures... ;’)


24 posted on 02/24/2008 8:57:48 AM PST by SunkenCiv (https://secure.freerepublic.com/donate/___________________Profile updated Tuesday, February 19, 2008)
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To: verum ago

http://www.freerepublic.com/focus/f-news/1641966/posts?page=234#234


25 posted on 02/24/2008 9:00:45 AM PST by SunkenCiv (https://secure.freerepublic.com/donate/___________________Profile updated Tuesday, February 19, 2008)
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To: kinoxi
I love it when they are wrong.

How are they wrong?

26 posted on 02/24/2008 9:03:52 AM PST by RightWhale (Clam down! avoid ataque de nervosa)
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To: neverdem

Thanks for the ping.


27 posted on 02/24/2008 9:03:53 AM PST by GOPJ (Do the editors of the L.A. Times realize that illegal immigration is, you know, illegal? Patterico)
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To: verum ago

How are they wrong?


28 posted on 02/24/2008 9:04:47 AM PST by RightWhale (Clam down! avoid ataque de nervosa)
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To: verum ago
I didn’t realize that by setting out to prove one’s explanation of an anomalous explanation by observing its effects was proper scientific conduct.

This is a very nebulous statement, and I am not sure exactly what you mean by "proper scientific conduct." To be clear science is about providing explanations of things that are observed. When the explanation is generalized to expand to multiple observations, instances, or circumstances then it becomes a "theory." The validity of the generalized explanation, i.e. theory, is predicated on its ability to explain a broad class of observations, and great weight is placed on a theory that predicts unexpected things that turn out to be true.

Thus, for instance theories of conservation of energy, entropy, the Maxwell equations, and so forth have become accepted theories. The phlogiston theory is no longer accepted as an adequate explanatory fit to observed phenomenon and therefore is discredited.

Anomolies are particularly valued in scientific practice because they provide the means to further validate a theory, modify a theory, restrict the domain of validity of a theory, develop a new theory for an entirely different phenomenon, or develop an expanded theory of greater validity than the original theory.

29 posted on 02/24/2008 9:06:08 AM PST by AndyJackson
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To: Eaker
Hmm, the Chandrasekhar uncertainty principle?
30 posted on 02/24/2008 9:24:40 AM PST by grey_whiskers (The opinions are solely those of the author and are subject to change without notice.)
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To: AndyJackson; RightWhale; SunkenCiv
from reply #11:
I was merely being humorously (to some) cynical about the price tags on many scientific endeavors and pieces of equipment, and about theoretical science— that which consists only of theory and observation, as opposed to experimental science— that which can falsified directly via experiment and not by the happy coincidence of something doing something that contradicts theory while we happen to be observing it. Which isn't to say that theoretical science is not without logic or utility.

*sighs* I guess I deserve some admonishment anyway...

... (you can set those beebers from 'reproach' back to 'safe'— I'll surrender peaceably.)
31 posted on 02/24/2008 11:46:15 AM PST by verum ago (The Iranian Space Agency: set phasers to jihad!)
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To: Robert A. Cook, PE
Half a planck...

(wink)

32 posted on 02/24/2008 11:51:33 AM PST by JasonC
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To: grey_whiskers
The sun rotates, slower than the earth it degrees a day but then it is much larger. The axis of its roration is nearly perpendicular to the plane of the orbits of the major planets, but is "off" by about 7 degrees from perfectly vertical. The speed of the rotation varies with the latitude, being fastest at the equator and slower at the poles. (Remember the sun surface is gas, like an atmosphere, not solid). The rotational period is about 25 days at the equator and about 36 days at the poles.
33 posted on 02/24/2008 11:56:02 AM PST by JasonC
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To: steve86
And when instead no gravitational waves are ever detected, despite the detectors getting more and more sensitive, what then?

When will the faith in the exactness of Einstein's gravity theory finally break down? I mean, if mere falsifying observations were enough, it would be dead as a doornail by now.

34 posted on 02/24/2008 12:11:02 PM PST by JasonC
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To: JasonC

“in” degrees per day - and “rotation” - darn typos, sorry for any confusion.


35 posted on 02/24/2008 12:12:03 PM PST by JasonC
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To: Strategerist
You and kinoxi obviously have a deep-seated contempt for scientists (and even the process of science, perhaps.) Why? What drives it?

Hope you don't mind if I butt in here ;^)

Let me start by suggesting anyone NOT finding major problems wihtin the scientific community™ should actually declare their religion. Since scientology is taken, I offer as a suggestion, denialogy. That is, you accept on faith everything promulgated that protects their sacred cows or sacred cowboys. There is a bold new world out there for all disciplines of science -- with the exception of anything that could disturb the status quo. It would appear to the layman, simple minded people have obtained control of the flow of scientific information.

If you're truly interested in discovering why there are a few around that distrust much of mainstream science, just have a look at mainstream media. Their incessant spreading of cow manure has been exposed for most of the world to see; maybe it's time the same be done for the scientific community™.

The PICTURE THAT WON'T GO AWAY.

36 posted on 02/24/2008 12:22:30 PM PST by ForGod'sSake (ABCNNBCBS: An enemy at the gates is less formidable, for he is known and carries his banner openly.)
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To: grey_whiskers; neverdem
IF the sun rotates, is it "exactly" in phase with the Earth? And does the sun's axis of rotation coincide with the axis of the Earth's orbit?

The answer to both questions is no.

The Sun's sidereal period of rotation is 25.35 days; its synodic period -- the time for it to make a full rovolution plus the additional time required for it to "catch up" to compensate for Earth's rotation along its orbit around the Sun -- is 27.25 days.

The plane of Earth's orbit around the Sun, known as the "ecliptic," is the fundamental plane of reference in our solar system. On star maps it is shown as a line that marks the Sun's apparent path against the background of the stars during the course of a year. Earth's axis of rotation is inclined 23.75 degrees off a perpendicular to the ecliptic; the Sun's rotational axis is inclined 7.25 degrees off a perpendicular to the ecliptic.

37 posted on 02/24/2008 12:23:05 PM PST by ngc6656
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To: RightWhale
How are they wrong?
If their models were correct this wouldn't be news.
"The bursts were completely unexpected," says astrophysicist and lead author Fotis Gavriil of NASA's Goddard Space Flight Center in Greenbelt, Maryland.
38 posted on 02/24/2008 2:11:07 PM PST by kinoxi
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To: ForGod'sSake; SunkenCiv

Halton Arp: A Modern Day Galileo

Halton Arp is to the 21st century what Galileo was to the 17th. Both were respected scientists, popular leaders in their field. Both made observations which contradicted the accepted theories. Seventeenth century academics felt threatened by Galileo's observations and so, backed by ecclesiastical authority, they ordered him to stop looking. Twentieth century astronomers felt threatened by Arp's observations and so, backed by institutional authority, they ordered him to stop looking.

Both refused. Both published works geared to the non-specialist when specialists would no longer take note. Galileo's paper, "A Dialogue on the Two Chief Systems of the World" , favored a heliocentric model of the solar system and undermined the accepted geocentric model. Arp's books, Quasars, Redshifts and Controversies, Seeing Red, and Catalogue of Discordant Redshift Associations, favor a steady-state model of the universe and undermine the accepted big bang model.

The Church responded by placing Galileo under house arrest: his peers would not even look through his telescope and the Church judged his books heretical. The modern astronomical community responded similarly to Arp. Observatory officials cancelled his telescope time and astronomical journals refused to publish his research...

LINK.

39 posted on 02/24/2008 2:14:09 PM PST by Fred Nerks (fair dinkum!)
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To: kinoxi

‘Unexpected’ is a fairly thin branch to decorate out like a righteous Christmas tree of anti-science rhetoric. Where did Galileo get off the track? Or if he didn’t, then where did Descartes fail to dig just a little deeper and miss paydirt?


40 posted on 02/24/2008 2:15:19 PM PST by RightWhale (Clam down! avoid ataque de nervosa)
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