By Devin Powell
Neutron stars, second only to black holes and pints of Guinness as the densest objects in the Universe, may have liquid in their cores, observations of a dead star shrouded in the debris of a distant supernova suggest. Two separate teams of scientists say that a frictionless state of matter called a superfluid is the only reasonable explanation for temperature changes recently observed in the youngest known neutron star.
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“This the first direct evidence for superfluidity in neutron stars,” says Wynn Ho, an astrophysicist at the University of Southampton in England and coauthor of a paper that will appear in the Monthly Notices of the Royal Astronomical Society describing one team’s findings. The other team’s results will appear in an upcoming Physical Review Letters.