Scientists know little about the interior of neutron stars, which contain about a Sun’s worth of mass packed in a sphere the size of a large city. Now, a new study says that neutron stars behave like fillings of chocolates. A neutron star is the dense, collapsed core of a massive star that exploded as a supernova, and is the densest object astronomers can observe directly. Since the discovery of neutron stars more than 60 years ago, scientists have been trying to decipher their structure. Simulating the extreme conditions inside neutron stars has been difficult because they can hardly be recreated on Earth in the laboratory.
Using equations of state, one can create models and describe properties such as density and temperature. An equation of state is an equation describing the state of matter and showing the relationship between physical conditions such as pressure, temperature, volume and internal energy. Scientists from Goethe University Frankfurt have used these equations to describe the structure of neutron stars from the stellar surface to the inner core.