Magnetic Hot Spots on Neutron Stars Survive for Millions of Years

A tightly wound-up magnetic field used as initial state in the simulation. Credit: K. Gourgouliatos, R. Hollerbach, U. Durham, U. Leeds

A tightly wound-up magnetic field used as initial state in the simulation. Credit: K. Gourgouliatos, R. Hollerbach, U. Durham, U. Leeds

A study of the evolution of magnetic fields inside neutron stars shows that instabilities can create intense magnetic hot spots that survive for millions of years, even after the star’s overall magnetic field has decayed significantly. The results will be presented by Dr Konstantinos Gourgouliatos of Durham University at the European Week of Astronomy and Space Science (EWASS) in Liverpool on Wednesday, 4th April.

When a massive star consumes its nuclear fuel and collapses under its own gravity in a supernova explosion, it can result in a neutron star. These very dense objects have a radius of about 10 kilometres and yet are 1...

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Finding Order in Disorder demonstrates a New State of Matter

This is Cristiano Nisoli. Credit: Los Alamos National Laboratory

This is Cristiano Nisoli. Credit: Los Alamos National Laboratory

‘Spindoctors’ note that topological order, associated with quantum mechanics, also applies to classical material called artificial spin ice. Physicists have identified a new state of matter whose structural order operates by rules more aligned with quantum mechanics than standard thermodynamic theory. In a classical material called artificial spin ice, which in certain phases appears disordered, the material is actually ordered, but in a “topological” form.

“Our research shows for the first time that classical systems such as artificial spin ice can be designed to demonstrate topological ordered phases, which previously have been found only in quantum conditions,” said Los Alamos National Laboratory physicist Cristiano Nisoli...

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X-rays could Sterilize Alien Planets in (otherwise) Habitable Zones

Artist’s impression of a red dwarf star orbited by an exoplanet. Credit: NASA/ESA/G. Bacon (STScI)

Artist’s impression of a red dwarf star orbited by an exoplanet. Credit: NASA/ESA/G. Bacon (STScI)

Intense radiation could strip away the ozone layer of Earth-like planets around other stars and render them uninhabitable, according to a new study led by Dr Eike Guenther of the Thueringer Observatory in Germany. Astronomers now know of around 4000 planets in orbit around other stars. A handful of these are both Earth-sized and in the habitable zones of the stars they orbit, where the temperature is right for liquid water.

But many candidate Earth-sized worlds are in orbit around red dwarf stars, much smaller and cooler than our own Sun. To be in the habitable zone, the planets need to be much closer to their stars than we are to the Sun...

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Gravitational Waves created by Black Holes in the Center of most galaxies

Sagittarius A*, the black hole at the centre of our own galaxy. Credit: NASA/CXC/MIT/F. Baganoff et al.

Sagittarius A*, the black hole at the centre of our own galaxy. Credit: NASA/CXC/MIT/F. Baganoff et al.

Gravitational waves may be forged in the heart of the galaxy, says a new study led by PhD student Joseph Fernandez at Liverpool John Moores University. He sets out the work in a presentation on 3rd April at the European Week of Astronomy and Space Science in Liverpool. Gravitational waves (GWs) are small ripples in space-time that spread throughout the universe.

When there is a change in air pressure on Earth, this change moves outwards in the form of sound waves. Analogously, when pairs of compact objects – like black holes (BHs) or neutron stars (NSs) – form binaries and rotate around one another, the gravitational field around them changes, producing GWs that also move outwards.

This ...

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