Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Quark star glimmers

11.04.2002


Space telescope may have spotted strange matter.
© NASA/Chandra


Astronomers may have discovered a strange new form of matter.

Astronomers think they might have spotted a quark star, a mass of fundamental particles only a few kilometres across but weighing more than our Sun. If the star’s nature is confirmed, it would be the first example of this state of matter.

Theoreticians hypothesized the existence of quark stars in the 1980s. Today, NASA announced the discovery of such a star, based on results from their space telescope the Chandra X-ray Observatory. The star, called RX J1856, is about 360 light years from Earth.



RX J1856 was previously thought to be a neutron star - these are formed when a large star explodes and collapses in on itself. Gravitational attraction between particles in an atom overcomes the electrical repulsion keeping them apart, fusing protons and electrons to form neutrons, which pack together at unimaginable density. A teaspoonful of neutron star would weigh a billion tons.

But Chandra’s measurements suggest that, at just over 11 kilometres across, RX J1856 is too small to be a neutron star, if current models are correct.

Instead, neutrons and protons in the star may themselves have dissolved into an even denser mass of their constituent quarks, suggests Jeremy Drake of the Harvard-Smithsonian Centre for Astrophysics in Cambridge, Massachusetts, and his colleagues1. This is known as strange matter, in which the packaging of three constituent quarks in a proton or neutron breaks down.

"Strange matter could be fairly common in the Universe," says Drake. It should be stable, and might grow like a crystal from the neutrons and protons it encounters. It’s possible, he adds, that all neutron stars are in fact quark stars. Drake declares himself "unbiased" about the star’s true identity.

But astronomer Frederick Walter of the State University of New York, Stony Brook, argues that the announcement is premature. Our ignorance of the star’s temperature and chemical composition make its diameter uncertain, he says.

"If it’s a quark star it’s spectacular, but there’s absolutely no evidence for that," Walter says. There is an alternative explanation: that variation in the star’s temperature makes it hard to estimate its diameter. The probability of this is less than 10%, as it would require the hottest part of the star to be pointing straight at Earth.

"These results are not definitive," agrees Michael Turner, an astrophysicist at the University of Chicago. Studies of other bodies are needed to confirm whether quark stars really exist, he says.

Chandra’s observations do show how the extreme regions of space can be used to test physical theories, adds Turner. "We can use the Universe as a heavenly laboratory."

References

  1. Drake, J. J. et al. Is RX J185635-375 a Quark Star?. Preprint, (2002).


JOHN WHITFIELD | © Nature News Service

More articles from Physics and Astronomy:

nachricht The taming of the light screw
22.03.2019 | Max-Planck-Institut für Struktur und Dynamik der Materie

nachricht Magnetic micro-boats
21.03.2019 | Max-Planck-Institut für Polymerforschung

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Solving the efficiency of Gram-negative bacteria

22.03.2019 | Life Sciences

Bacteria bide their time when antibiotics attack

22.03.2019 | Life Sciences

Open source software helps researchers extract key insights from huge sensor datasets

22.03.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>