MessageToEagle.com - Many mysteries regarding neutron stars have to be solved and one of such mysteries has just been revealed,
the first direct evidence for this bizarre state
of matter in the core of a neutron star.
Neutron stars contain the densest known matter that is directly observable. One teaspoon of neutron star material weighs six billion tons.
X-ray Observatory has discovered the first direct evidence for a superfluid, a bizarre, friction-free state of matter, at the core of a neutron star.
Superfluids created in laboratories on Earth exhibit remarkable properties, such as the ability to climb upward and escape airtight containers.
The finding has important implications for understanding nuclear interactions in matter at the highest known densities.
The pressure in the star's core is so high that most of the charged particles, electrons and protons, merge resulting
in a star composed mostly of uncharged particles called neutrons.
Two independent research teams studied the supernova remnant Cassiopeia A, or Cas A for short, the remains of a massive
star 11,000 light years away that would have appeared to explode about 330 years ago as observed from Earth.
Chandra data found a rapid decline in the temperature of the ultra-dense neutron star that remained after the supernova,
showing that it had cooled by about four percent over a 10-year period.
"This drop in temperature, although it sounds small, was really dramatic and surprising to see," said Dany Page of
the National Autonomous University in Mexico, leader of a team with a paper published in the February
25, 2011 issue of the journal Physical Review Letters.
"This means that something unusual is happening within this neutron star."
Superfluids containing charged particles are also superconductors, meaning they act as perfect electrical conductors and never lose energy. The new results strongly suggest that the remaining protons in the star's core are in a superfluid state and, because they carry a charge, also form a superconductor.
This composite image shows a beautiful X-ray and optical view of Cassiopeia A (Cas A), a supernova remnant located
in our Galaxy about 11,000 light years away. These are the remains of a massive star that exploded about 330 years
ago, as measured in Earth's time frame. X-rays from Chandra are shown in red, green and blue along with optical
data from Hubble in gold. At the center of the image is a neutron star, an ultra-dense star created by the supernova.
Ten years of observations with Chandra have revealed a 4% decline in the temperature of this neutron star, an
unexpectedly rapid cooling. Two new papers by independent research teams show that this cooling is likely
caused by a neutron superfluid forming in its central regions, the first direct evidence for this bizarre state
of matter in the core of a neutron star. Credits: X-ray: NASA/CXC/xx; Optical: NASA/STScI; Illustration: NASA/CXC/M.Weiss
"The rapid cooling in Cas A's neutron star, seen with Chandra, is the first direct evidence that the cores of these neutron stars are, in
fact, made of superfluid and superconducting material," said Peter Shternin of the Ioffe Institute in St Petersburg, Russia, leader of a
team with a paper accepted in the journal Monthly Notices of the Royal Astronomical Society.
Both teams show that this rapid cooling is explained by the formation of a neutron superfluid in the core of the neutron star within about
the last 100 years as seen from Earth. The rapid cooling is expected to continue for a few decades and then it should slow down.
Watch a brief animation of Cas A's neutron star:
"It turns out that Cas A may be a gift from the Universe because we would have to catch a very young neutron star at just the right point
in time," said Page's co-author Madappa Prakash, from Ohio University. "Sometimes a little good fortune can go a long way in science."
The onset of superfluidity in materials on Earth occurs at extremely low temperatures near absolute zero, but in neutron stars, it can occur
at temperatures near a billion degrees Celsius. Until now there was a very large uncertainty in estimates of this critical temperature.
This new research constrains the critical temperature to between one half a billion to just under a billion degrees.
Cas A will allow researchers to test models of how the strong nuclear force, which binds subatomic particles, behaves in ultradense matter.
These results are also important for understanding a range of behavior in neutron stars, including "glitches," neutron star precession and
pulsation, magnetar outbursts and the evolution of neutron star magnetic fields.
Small sudden changes in the spin rate of rotating neutron stars, called glitches, have previously given evidence for superfluid neutrons in
the crust of a neutron star, where densities are much lower than seen in the core of the star. This latest news from Cas A unveils new
information about the ultra-dense inner region of the neutron star.
"Previously we had no idea how extended superconductivity of protons was in a neutron star," said Shternin's co-author Dmitry Yakovlev, also
from the Ioffe Institute.
The cooling in the Cas A neutron star was first discovered by co-author Craig Heinke, from the University of Alberta, Canada, and Wynn Ho from
the University of Southampton, UK, in 2010. It was the first time that astronomers have measured the rate of cooling of a young neutron star.
Page's co-authors were Prakash, James Lattimer (State University of New York at Stony Brook), and Andrew Steiner (Michigan State University.)
Shternin's co-authors were Yakovlev, Heinke, Ho, and Daniel Patnaude (Harvard-Smithsonian Center for Astrophysics.)
Abnormal Star Discovered In The 'Forbidden Zone'
A team of astrophysicists from Germany, France and Italy have discovered in the constellation Leo is an old star.
The star's existence raised at once many questions for scientists.
The object is definitely not as its "contemporaries" that appeared immediately after the Big Bang event.
Never Ending Winter In Our Solar System
There's no lack of ice in our solar system.
Frozen water can be found almost everywhere: the poles of Mercury, Earth, the moon and Mars; the rings and icy satellites of the outer planets;
and in comets that come whizzing past.
Winter in our Solar system is not as we know it on our planet.
The Eyes Of A Future Alien Astronomer - What Will They See?
Have you ever wondered what the Universe will look like for a future alien astronomer?
It will in fact be entirely different from what it is today.
One trillion years from now, an alien astronomer in our galaxy will have great difficulties figuring out how the universe began...
Possible Water In The Atmosphere Of A Super-Earth
Four CfA astronomers, Zachory Berta, David Charbonneau, Jean-Michel Desert, and Jonathan Irwin, together with six colleagues,
used the Hubble Space Telescope to probe the atmosphere around the transiting super-Earth known as GJ1214b.
This exoplanet has a mass of 6.5 Earth-masses and a radius of 2.7 Earth-radii, and it orbits a small M-dwarf star (its diameter
is only 21% of the Sun's).
Astronomical Mystery - Tremendous Explosion And Appearance Of Odd Rings
Twenty five years ago, on 1987 February 23, the brightest supernova of modern times was observed in the Large Magellanic Cloud.
The collision occurred at speeds near 60 million kilometers per hour and shock-heats the ring material causing it to glow.
Over time, astronomers have watched and waited for the expanding debris from this tremendous stellar explosion to crash into previously expelled material...
Why Do We See The Man In The Moon?
There’s something poetic about gazing up at the night sky, seeing the familiar face of the “Man in the Moon” who faithfully accompanies us through life.
The synchronous rotation of the Moon - it takes the same amount of time to spin around its own axis as it does to revolve around Earth -
is what causes the Moon to "lock eyes" with Earth.
Watching Volcanoes On Alien Worlds
Volcanoes display the awesome power of nature like few other events.
Now that astronomers are finding rocky worlds orbiting distant stars, they're asking the next logical questions:
Do any of those worlds have volcanoes? And if so, could we detect them?
Powerful Jet Pointing Directly At Earth
They are among the most fascinating cosmic phenomena. Astronomers know them as blazars and each of them harbors a supermassive black hole and jets emanating
in opposite directions from near its poles. These sources are unique evidence of the most extreme speeds and energies known in the extreme Universe...
Doesn't Secret Dark Matter Exist?
The more scientists study dark matter they know lesser and are not particularly optimistic about their results.
After completing this study, we know less about dark matter than we did before," said Matt Walker, of the Harvard-Smithsonian Center for Astrophysics.
A mysterious and still unknown substance is totally invisible in the Universe and reveals its presence only through its gravitational pull...
Dwarf Irregular Galaxy That Forces Scientists To Re-Evaluate Old Theory
Astronomers from Center for Astrophysics of the University of Porto, Portugal and Oskar Klein Centre, Stockholm University, Sweden come up
with new findings regarding one of the most studied objects - the dwarf galaxy I Zw 18.
The results led the scientists to the conclusion that this enigmatic blue compact dwarf might force
astronomers to review current galaxy formation models and much of what is known about galaxy formation and evolution might need substantial revision.
Violent Dragon Clash Billions Of Years Ago
NGC 5907 is sometimes called the "Splinter" or Knife Edge Galaxy because of its unusual appearance.
It is a spiral galaxy lying in the Dragon constellation,
about 40 million light-years from Earth that could have been formed through a gigantic collision of galaxies, 8 to 9 billion years ago.