When a neutron star forms, the immense gravitational pressure causes the collapse of a massive star's core. During this collapse, protons and electrons are squeezed together to form neutrons through a process called electron capture. Essentially, some protons in the core absorb electrons and combine to form neutrons and neutrinos. This process continues until the core is composed primarily of densely packed neutrons.
In a neutron star, the majority of protons have transformed into neutrons. However, not all protons are converted, and a small fraction may still remain in the form of a neutron star. These remaining protons are known as "drip protons" or "neutron drip," as they are believed to drip out of the neutron star due to their mutual repulsion.
The resulting material of a neutron star is incredibly dense and exotic. Neutron stars are among the densest objects in the universe, with masses greater than that of the Sun compressed into a sphere roughly the size of a city. The material is mainly composed of densely packed neutrons, with a small fraction of remaining protons and some electrons.
Due to its extreme density, the gravitational pull on the surface of a neutron star is incredibly strong. This results in intense gravitational forces, making the material extremely compact and causing it to exhibit peculiar properties. For example, the surface of a neutron star is typically solid and composed of a lattice-like structure, with a crust made up of atomic nuclei and a sea of electrons.
The gravity on a neutron star is so intense that it distorts the fabric of spacetime around it. This leads to effects like time dilation and the warping of light. Additionally, the intense gravitational pull creates extremely high pressures and magnetic fields on the surface, which can give rise to various exotic phenomena, such as pulsars and magnetars.
Given their extreme conditions, it is difficult to imagine what a neutron star would feel like if one could somehow touch it. However, it is safe to say that due to the immense gravitational forces, any object approaching a neutron star would be crushed and torn apart long before physical contact could occur.