The Pole star comes to life again

Jul 21, 2008
Artist's impression of Polaris and the constellations of the Big and Small Dippers.

(PhysOrg.com) -- The Northern Star, whose vibrations were thought to be dying away, appears to have come to life again.

An international team of astronomers has observed that vibrations in the Pole star, which had been fading away to almost nothing over the last hundred years, have recovered and are now increasing. And the astronomers don't know why.

Plot of decrease over 100 years of amplitude of 4-day light variation of Polaris and of the increase since 2000. Observations before 2000 from other work, observations after 2000 from this work.

The discovery will be announced during the "Cool Stars 15" conference at the University of St Andrews. Dr Alan Penny from the School of Physics and Astronomy will present results of the recovery to around 350 international delegates at the meeting that runs from July 21-25.

The astronomers were watching Polaris in the expectation that they would catch the star switching off its vibrations completely when they made the surprising observation of its revival.

Dr Penny explained, "It was only through an innovative use of two small relatively unknown telescopes in space and a telescope in Arizona that we were able to discover and follow this star's recovery so accurately."

Team leader, Dr Hans Bruntt of the University of Sydney, had been using a small telescope attached to NASA's now defunct infrared space telescope (WIRE) to study the star for a short period of time. He knew Dr Penny was using a device known as the SMEI space camera - predominately employed to watch matter being ejected from the Sun - to do long-term monitoring of stars. When the SMEI data were analysed this recovery of Polaris was seen, and could also be traced in the WIRE data.

Professor Joel Eaton of Tennessee State University was also doing long-term monitoring, and, using the AST automated spectroscopic telescope located in Arizona, was able to confirm the observations of Polaris by watching the change in velocity of the surface of the star as the variation caused it to expand and contract.

Although Shakespeare's Julius Caesar declared, "I am as constant as the Northern star, Of whose true-fix'd and resting quality There is no fellow in the firmament", Polaris is a 'Cepheid' variable star, getting brighter and fainter every four days. Cepheids do play a vital part as 'standard candles' in determining the size of the Universe, but the details of their variations are not well understood.

Dr Penny said, "One hundred years ago Polaris varied by 10%, but over the last century the variations became smaller and smaller until ten years ago it only varied by 2%.

"It was thought the structure of the star was changing to switch off the vibration. Yet the team has found that about ten years ago the vibrations started picking up and are now back up at the 4% level."

The slow decline in variability was in itself unusual, as no other Cepheid is known to do this. Astronomers thought that Polaris was ageing and its structure was changing so that it was no longer unstable. This was being followed to learn about how stars age. Now Polaris has 'turned on' again this explanation seems unlikely and there may be a complex process in the outer layers of the star, with more than one mode of variability.

The paper will be published in the Aug 10 edition of the 'Astrophysical Journal'. A pre-publication paper is available on arxiv.org/abs/0804.3593

Provided by University of St Andrews

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User comments : 7

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tkjtkj
4.8 / 5 (5) Jul 21, 2008
Interesting .. But no mention is made of the made of the fact that Polaris is
a binary star system ... That fact
seems ignored in spite of the
consequence that 'vibrations' might
be an attribute of some binary
systems.
Arikin
5 / 5 (4) Jul 21, 2008
I thought that the Hubble telescope (in 2006?) found that Polaris is a triple star system. One star being extremely close to the main star.

But that still leaves the question of why this isn't mentioned in this article like tkjtkj says.
seanpu
5 / 5 (3) Jul 22, 2008
it is a triple star system http://hubblesite...2006/02/
menkaur
not rated yet Jul 22, 2008
how about planets, passing in front of that star?
would it explain it?
THEY
2.2 / 5 (5) Jul 22, 2008
It is a Physorg article. Their reporting is now as much garbage as their forum. It figures that the facts are WEAK.
Mercury_01
3 / 5 (2) Jul 22, 2008
long live the mighty polaris!
omatumr
4 / 5 (4) Jul 27, 2008
Variations in Earth's climate and in luminosity of the Sun and other stars has been a mystery because astrophysicists have blindly insisted that Hydrogen-fusion is the energy source.

However, recent research findings in nuclear physics are about to destroy the illusion that stars are balls of Hydrogen.

About sixty-five (65) nuclear physicists at Brookhaven National Laboratory, the Thomas Jefferson National Accelerator Facility and several other leading research facilities and universities around the world, including MIT, have cautiously confirmed strongly repulsive forces between neutrons.

This signals the certain demise of the standard model of Hydrogen-filled stars.

In the spring semester of 2000 five graduate students (Cynthia Bolon, Shelonda Finch, Daniel Ragland, Matthew Seelke and Bing Zhang) and I made this three-dimensional (3-D) plot of the rest masses of the 3,000 different types of atoms that constitute all visible matter in the universe:

http://www.omatumr.com/Data/2000Data.htm" title="http://http://www.omatumr.com/Data/2000Data.htm" rel="nofollow" target="_blank">http://www.omatum...Data.htm

This "Cradle of the Nuclides" showed that neutron-proton interactions are attractive, unlike proton-proton and neutron-neutron interactions [1], and exposed repulsive forces between neutrons as the energy source that powers the Sun, ordinary stars, neutron stars, and the cosmos [2-10].

In this new report from Brookhaven National Laboratory [11] four nuclear physicists report that:

A. Nucleons "repel each other strongly" at close distances.

B. "In nature there exists another way to create dense nuclear matter by using another force to overcome the strong inter-nucleon repulsion at short distances. Neutron stars . . . . . This dense nuclear matter is created by the large gravitational force, which adds the necessary compression."

C. "The difference between neutron-proton and neutron-neutron or proton-proton pairs is due to the nature of the nucleon-nucleon interaction. The tensor force in the neutron-proton interaction, which is missing in the neutron-neutron or proton-proton interaction, is probably what creates the difference between cold dense matter of nucleons of the same kind, and cold dense matter of mixed nucleons."

D. "These surprising new results were confirmed in a higher-precision experiment completed recently at Jefferson Laboratory in Virginia."

The results of measurements at Jefferson Laboratory were recently published in the 13 June 2008 issue of Science magazine [12].

This paper stresses the high number of neutron-proton pairs in Carbon-12 from attractive neutron-proton interactions.

Apparently unaware of the Sun's neutron-rich core, the last sentence of the abstract notes that their findings may be of general interest to astrophysics: "This difference between the types of pairs is due to the nature of the strong force and has implications for understanding cold dense nuclear systems such as neutron stars."

With kind regards,
Oliver K. Manuel
http://www.omatumr.com
http://myprofile....anuelo09

REFERENCES:

01. O. Manuel, C. Bolon, A. Katragada, and M. Insall, "Attraction and repulsion of nucleons: Sources of stellar energy", Journal of Fusion Energy 19 (2001) pp. 93-98.

http://www.omatumr.com/abstracts/jfeinterbetnuc.pdf

02. O. Manuel, C. Bolon, M. Zhong, and P. Jangam, "The Sun's origin, composition and source of energy", Abstract 1041 , 32nd Lunar and Planetary Science Conf., Houston, TX, March 12-16, 2001, LPI Contribution 1080 (2001) ISSN No. 0161-5297.

http://www.lpi.us...1041.pdf

03. O. Manuel, E. Miller, and A. Katragada, "Neutron repulsion confirmed as energy source",Journal of Fusion Energy 20 (2002) 197-201.

http://www.omatumr.com/abstracts2003/jfe-neutronrep.pdf

04. O. Manuel, C. Bolon, and M. Zhong, "Nuclear systematics: III. The source of solar luminosity", Journal of Radioanalytical & Nuclear Chemistry 252 (2002) 3-7.

http://www.omatumr.com/abstracts2001/nuc_sym3.pdf

05. O. Manuel, "The standard solar model versus experimental observations", Proceedings of the 3rd International Conference on Beyond Standard Model Physics - BEYOND 2002 (IOP, Bristol, editor: H. V. Klapdor-Kleingrothaus, 2003) pp. 307-316.

http://www.omatumr.com/abstracts/beyond2002.pdf

06. O. Manuel and Stig Friberg, "Composition of the solar interior: Information from isotope ratios", Proceedings of the SOHO/GONG 2002 Conference on Local and Global Helio-seismology: The Present and the Future, 27 Oct-1 Nov 2002, Big Bear Lake, CA, U.S.A. (ESA SP-517, editor:
Huguette Lacoste, 2003) pp. 345-348. ISBN: 92-9092-827-1

http://arxiv.org/...410717v1

07. O. Manuel, Barry Ninham, and Stig Friberg, "Super-fluidity in the solar interior: Implications for solar eruptions and climate", Journal of Fusion Energy 21 (2002) 193-198.

http://arxiv.org/.../0501441

08. O. Manuel, M. Mozina, and H. Ratcliffe, "On the cosmic nuclear cycle and the similarity of nuclei and stars", Journal of Fusion Energy 25 (2006) 107-114; DOI:10.1007/s10894-006-9009-6

http://xxx.lanl.g.../0511051

09. O. Manuel, S. A. Kamat, and M. Mozina, "The Sun is a plasma diffuser that sorts atoms by mass", Physics of Atomic Nuclei 69 (2006) pp. 1847-1856; ISSN 1063-7788.

http://arxiv.org/.../0609509

10. Hilton Ratcliffe, "The Virtue of Heresy: Confessions of a Dissident Astronomer" (Author House, 2007) 408 pp.; ISBN: 978-1-4343-0727-9

11. Yousef Makdisi, Eli Piasetzky, John Watson and Mark Strikman, "The Study of Cold, Dense Nuclear Matter at BNL", Brookhaven National Laboratory
http://www.bnl.go...tter.pdf]www.bnl.gov/bnlwe...tter.pdf[/url] Probing Cold Dense Nuclear Matter&hl=en&ct=clnk&cd=6&gl=us" target="_blank">http://64.233.167.104/search?q=cache:TCNi4vA5KCcJ:http://www.bnl.go...tter.pdf]www.bnl.gov/bnlwe...tter.pdf[/url] Probing Cold Dense Nuclear Matter&hl=en&ct=clnk&cd=6&gl=us

or http://tinyurl.com/5tg4tv

or http://http://www.bnl.go...tter.pdf]www.bnl.gov/bnlwe...tter.pdf[/url]

12. R. Subedi and 63 co-authors, "Probing cold dense nuclear matter", Science (13 June 2008) 320, pp. 1476 - 1478. DOI: 10.1126/science.1156675

http://www.scienc...6?ck=nck

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