Neutron Star Mystery Heats Up with New Study

For years, scientists believed they knew quite a bit about neutron stars, the super dense stars that form when a large star explodes and its core collapses into itself. Now, though, it turns out that they may have to rethink the way they thought the surface of a neutron star can heat itself up. It turns out that new findings have led them to believe that there's another mechanism at play when it comes to these stars.

Scientists have long thought that nuclear reactions within the crusts of neutron stars contributed to heating of the stars' surfaces. It turns out, though, that this may not be the case. The researchers have performed theoretical calculations that identify previously unknown layers where nuclear reactions within the crust cause rapid neutrino cooling. These neutrinos are elementary particles created through radioactive decay that pass quickly through matter.

"These cooling layers are pretty shallow beneath the surface," said Hendrik Schatz, one of the researchers, in a news release. "If heat from deeper within the star comes up, it hits this layer and never makes it to the surface. This completely changes the way we think about the question of the star's hot surface. It's a big puzzle now."

In fact, the latest findings produce more questions than answers. On a sub-atomic level, the process is greatly affected by the shape of reacting nuclei. Yet further research is likely needed before scientists can figure out exactly what's happening to heat up the star's surface.

"Many nuclei are round, and that suppresses the neutrino cooling," said Sanjib Gupta, one of the researchers, in a news release. "In this case, the nuclei are predicted by theorists to be 'deformed' more football-shaped."

The findings reveal a little bit more about neutron stars--or at least show what processes aren't at play. Currently, researchers are looking forward to find out exactly how neutron stars heat themselves up if they have to face this type of cooling behavior. This, in turn, could help inform future models of stars and galaxies alike.