Science Current Events | Science News | Brightsurf.com
 
Email a Friend Send to a friend
Printer Friendly Print Neutron stars warp space-time, U-M astronomers observe
Slashdot It! Slashdot Neutron stars warp space-time, U-M astronomers observe
Submit to Reddit Submit Neutron stars warp space-time, U-M astronomers observe to Reddit
Reading: Neutron stars warp space-time, U-M astronomers observeTwitter This Reading: Neutron stars warp space-time, U-M astronomers observeTwitter Neutron stars warp space-time, U-M astronomers observe
Add to Facebook Add Neutron stars warp space-time, U-M astronomers observe to Facebook

Neutron stars warp space-time, U-M astronomers observe

August 29, 2007

ANN ARBOR, Mich.---Einstein's predicted distortion of space-time occurs around neutron stars, University of Michigan astronomers and others have observed. Using European and Japanese/NASA X-ray observatory satellites, teams of researchers have pioneered a groundbreaking technique for determining the properties of these ultradense objects.

Neutron stars contain the densest observable matter in the universe. They cram more than a sun's worth of material into a city-sized sphere, meaning a few cups of neutron-star stuff would outweigh Mount Everest. Astronomers use these collapsed stars as natural laboratories to study how tightly matter can be crammed under the most extreme pressures nature can offer.




Researchers who study neutron stars are seeking answers to fundamental physics questions. Their centers could hold exotic particles or states of matter that are impossible to create in a lab.

The first step in addressing these mysteries is to accurately and precisely measure the diameters and masses of neutron stars. A U-M study is one of two that have recently done just that.

Like neutron stars themselves, the region around these stars is also extreme. The motions of gas in this environment are described by Einstein's general theory of relativity. Scientists are now exploiting general relativity to study neutron stars.

U-M research fellow Edward Cackett and assistant professor Jon Miller are lead authors of a paper on the research that has been submitted to Astrophysical Journal Letters. Independent work reported by Sudip Bhattacharyya and Tod Strohmayer of NASA's Goddard Space Flight Center bolsters the results reported by Cackett and Miller, and together the results signal that an accessible new method for probing neutron stars has been found.

NASA describes the findings as "a big step forward."

Cackett and Miller used the Japanese/NASA Suzaku X-ray observatory satellite to survey three neutron-star binaries: Serpens X-1, GX 349+2, and 4U 1820-30. The team studied the spectral lines from hot iron atoms that are whirling around in a disk just beyond the neutron stars' surface at 40 percent light speed.

Previous X-ray observatories detected iron lines around neutron stars, but they lacked the sensitivity to measure the shapes of the lines in detail.

Cackett and Miller, along with the Goddard astronomers, were able to determine that the iron line is broadened asymmetrically by the gas's extreme velocity. The line is smeared and distorted because of the Doppler effect and beaming effects predicted by Einstein's special theory of relativity. The warping of space-time by the neutron star's powerful gravity, an effect of Einstein's general theory of relativity, shifts the neutron star's iron line to longer wavelengths.

The iron line Cackett and Miller observed in Serpens X-1 was nearly identical to the one Bhattacharyya and Strohmayer observed with a different satellite: the European Space Agency's XMM-Newton. In the other star systems, Cackett and Miller observed similarly-skewed iron lines.

"We're seeing the gas whipping around just outside the neutron star's surface," Cackett said. "And since the inner part of the disk obviously can't orbit any closer than the neutron star's surface, these measurements give us a maximum size of the neutron star's diameter. The neutron stars can be no larger than 18 to 20.5 miles across, results that agree with other types of measurements."

Knowing a neutron star's size and mass allows physicists to describe the "stiffness," or "equation of state," of matter packed inside these incredibly dense objects. Besides using these iron lines to test Einstein's general theory of relativity, astronomers can probe conditions in the inner part of a neutron star's accretion disk.

"Now that we've seen this relativistic iron line around three neutron stars, we have established a new technique," Miller said. "It's very difficult to measure the mass and diameter of a neutron star, so we need several techniques to work together to achieve that goal."

University of Michigan





Science News and Science Current Events Tag Cloud
This tag cloud is a visual representation of term frequencies of random science news topics with common terms grouped together and emphasized by their display size.
Comet   Lupus   Health Care   Gamma Ray   General Relativity   Muscular Dystrophy   Robotic Surgery   Arsenic   Smart-1   Pesticide   Organic Matter   Cosmic Dust   Stratosphere   Obstructive Sleep Apnea   Glioblastoma   Caesarean Section   Working Memory   Chimpanzees   Large Hadron Collider   Salmonella   Emissions   Parasite   Autophagy   Galaxy Clusters   Biosensor  
Related Neutron Stars Current Events and Neutron Stars News Articles Neutron Stars Current Events and Neutron Stars News RSS Neutron Stars Current Events and Neutron Stars News RSS
European Satellites Probe a New Magnetar
On Aug. 22, 2008, NASA's Swift satellite reported multiple blasts of radiation from a rare object known as a soft gamma repeater, or SGR.

The cosmos is green: Researchers catch nature in the act of 'recycling' a star
For the first time, researchers have observed a singular cosmic act of rebirth: the transformation of an ordinary, slow-rotating pulsar into a superfast millisecond pulsar with an almost infinitely extended lifespan.

Astronomers catch a star being revved-up
Researchers have witnessed a star being transformed into an object that spins at almost 600 times a second using telescopes in the USA and the Netherlands, and CSIRO's Parkes telescope in Australia.

Star crust 10 billion times stronger than steel, IU physicist finds
Research by a theoretical physicist at Indiana University shows that the crusts of neutron stars are 10 billion times stronger than steel or any other of the earth's strongest metal alloys.

A young pulsar shows its hand
A small, dense object only twelve miles in diameter is responsible for this beautiful X-ray nebula that spans 150 light years.

NASA's Swift, Fermi Probe Fireworks From a Flaring Gamma-Ray Star
Astronomers using NASA's Swift satellite and Fermi Gamma-ray Space Telescope are seeing frequent blasts from a stellar remnant 30,000 light-years away.

Space engineers from India work with University of Leicester for first national astronomy satellite
India's first national Astronomy satellite- Astrosat- is to have key components assembled by the University of Leicester.

NSF / NASA 'Firefly' CubeSat Mission to Study Link Between Lightning and Terrestrial Gamma Ray Flashes
Massive energy releases occur every day in the upper reaches of Earth's atmosphere. Lightning may give rise to these bursts of radiation. However, unlike the well-known flashes of light and peals of thunder familiar to Earth-dwellers, these energy releases are channeled upward and can be detected only from space.

First gamma-ray-only pulsar observation opens new window on stellar evolution
About three times a second, a 10,000-year-old stellar corpse sweeps a beam of gamma-rays toward Earth.

NASA'S Fermi Telescope Discovers First Gamma-Ray-Only Pulsar
About three times a second, a 10,000-year-old stellar corpse sweeps a beam of gamma-rays toward Earth. Discovered by NASA's Fermi Gamma-ray Space Telescope, the object, called a pulsar, is the first one known that only "blinks" in gamma rays.
More Neutron Stars Current Events and Neutron Stars News Articles
Black Holes, White Dwarfs and Neutron Stars: The Physics of Compact Objects

Black Holes, White Dwarfs and Neutron Stars: The Physics of Compact Objects
by Stuart L. Shapiro (Author), Saul A. Teukolsky (Author)

Black holes, White Dwarfs, and Neutron Stars The physics of Compact Objects Compact objects—black holes, white dwarfs, and neutron stars—are fundamental constituents of the physical universe. They are born when normal stars die. This book is a product of the recent explosion of scientific activity centering on these objects. This self-contained work is a rigorous, yet understandable, references on the latest theoretical and observational developments. It is at once an outstanding text for graduate and advanced undergraduate students in physics, and a practical self-study guide for scientists in other disciplines and scientifically-oriented laypersons. No prior knowledge of astrophysics or relativity theory is required. Compact objects provide unique cosmic laboratories for testing...

Neutron Stars 1: Equation of State and Structure (Astrophysics and Space Science Library) (v. 1)

Neutron Stars 1: Equation of State and Structure (Astrophysics and Space Science Library) (v. 1)
by P. Haensel (Author), A.Y. Potekhin (Author), D.G. Yakovlev (Author)

The book gives an extended review of theoretical and observational aspects of neutron star physics. With masses comparable to that of the Sun and radii of about ten kilometres, neutron stars are the densest stars in the Universe. This book describes all layers of neutron stars, from the surface to the core, with the emphasis on their structure and equation of state. Theories of dense matter are reviewed, and used to construct neutron star models. Hypothetical strange quark stars and possible exotic phases in neutron star cores are also discussed. Also covered are the effects of strong magnetic fields in neutron star envelopes and a comparison on neutron star models with observations.

  Neutron Star [A Beowulf Shaeffer Story]
by Fictionwise Classic

One of Niven's most beloved characters, Beowulf Shaeffer, is forced to take a dangerous mission to explore a neutron star. The last group who went there never came back alive, but Shaeffer faces life imprisonment if he doesn't take the job. Will he determine the mysterious force that turned the prior crew to hamburger before he suffers a similar fate? Hugo Award Winner

Neutron Stars and Pulsars (Astrophysics and Space Science Library)

Neutron Stars and Pulsars (Astrophysics and Space Science Library)
by Werner Becker (Author), Werner Becker (Editor)

Neutron stars are the most compact astronomical objects in the universe which are accessible by direct observation. Studying neutron stars means studying physics in regimes unattainable in any terrestrial laboratory.

Understanding their observed complex phenomena requires a wide range of scientific disciplines, including the nuclear and condensed matter physics of very dense matter in neutron star interiors, plasma physics and quantum electrodynamics of magnetospheres, and the relativistic magneto-hydrodynamics of electron-positron pulsar winds interacting with some ambient medium. Not to mention the test bed neutron stars provide for general relativity theories, and their importance as potential sources of gravitational waves. It is this variety of disciplines which, among...

Neutron Star 

Neutron Star 
by Kobalt Digital Licensing



Black Hole Star/Tales from the Blues Cocoons

Black Hole Star/Tales from the Blues Cocoons
by Neutrons



Jimmy Neutron:  Boy Genius

Jimmy Neutron: Boy Genius
by THQ

Jimmy Neutron: Boy Genius tells the story of a 10-year-old boy who, along with his robot dog Goddard, battles evil, rescues his parents from aliens, saves Earth, and still makes it home in time for supper. The game features tons of techno gadgets, including a laser gun, shrink ray, asthma spray, and missiles. The game features multiplayer character abilities for Jimmy, Goddard, Carl, Nick, Dad, Cindy, and Ultra Lord. Areas include Retroville, a meteor storm, the Yokian moon, and a Yokian chase through space.

Neutron Star

Neutron Star
by Larry Niven (Author)

Come to Larry Niven's Universe and meet all the natives: Thrints, Bandersnatchi, Puppeteers -- and a host of other wonderfully created characters.
Visit Lookitthat, Down, and Jinx -- indeed, an entire galaxy of planets found only in these stories that trace man's expansion and colonization throughout Known Space.
A spectacular cycle of the future . . . a 10,000-year history of man on Earth and in space!


Jets of Material Shooting out from the Neutron Star in the Binary System 4U 0614+091 Astronomy & Space Photographic Poster Print by Stocktrek Images, 32x24

Jets of Material Shooting out from the Neutron Star in the Binary System 4U 0614+091 Astronomy & Space Photographic Poster Print by Stocktrek Images, 32x24
by Art.com

Art.com is the world's largest retailer of art prints, posters, photographs, and framed artwork. With our huge selection of over 400,000 prints, you'll easily find the perfect piece for your home, office, or classroom. Our art is printed on quality paper. When you order framed artwork, the piece is built by our team of in-house professionals. Visit our Amazon store today at www.amazon.com/artdotcom to find Special Offers and search for products based on 'Artist Name' and 'Subject Categories' such as Movie, Music, Vintage, TV, Children, Travel, Kitchen, Museum Art, Animals, Floral, Motivational, and Sports. Art.com is dedicated to providing you with high quality products and service by offering you 100% satisfaction guaranteed. We ship internationally to over 80 countries. Decorate your...

Physics of Neutron Star Interiors (Lecture Notes in Physics)

Physics of Neutron Star Interiors (Lecture Notes in Physics)
by Springer

Neutron stars are the densest observable bodies in our universe. Born during the gravitational collapse of luminous stars - a birth heralded by spectacular supernova explosions - they open a window on a world where the state of the matter and the strengths of the fields are anything but ordinary. This book is a collection of pedagogical lectures on the theory of neutron stars, and especially their interiors, at the forefront of current research. It addresses graduate students and researchers alike, and should be particularly suitable as a text bridging the gap between standard textbook material and the research literature.

© 2009 BrightSurf.com