Neutron stars

                      A rotating neuron star also known as pulsar( artists view).                                                                                                                                                       A celestial object of very small radius, typically 30Km and very high density, compound predominantly of closed packed neutrons. When any star of mass nearly 10-29 Solar masses start to collapse at the end of their life, in supernova they flushes out all the electrons , protons, neutrinos and many other particles, they remained only with neutrons yielding the name Neutron star. Neutron stars are the smallest and densest stars not counting Black holes , Quark stars , hypothetical White holes and strange stars . They are formed only by those stars whose masses is insufficient to produce a Black hole.     

                        A neutron star captured by high resolution telescope.                                                                                                                                                               The density of Neutron star is in order of 10^17 Kgm^-3 (density of atomic nuclei) . They cool over time and are not actively generating heat. Magnetic field of a Neutron star is 10^18-10^15 times stronger than Earth's magnetic field and it's gravitational field is approximately 2×10^11 times stronger than Earth . Neutron stars are partially supported against further collapse by Neutron degeneracy pressure, a phenomena described by Pauli Exclusive Principle, just as White drawfs are supported against collapse by electron degeneracy pressure but neutron degeneracy pressure is not sufficient to hold up an object beyond 0.7M(M=solar mass) , nuclear force play a large role in supporting more massive Neutron stars. Due to conservation of Angular Momentum, the rotation rate of a Neutron star is directly proportional to collapsion rate of its core. A rotating Neutron star which emits Electromagnetic waves are called Pulsars . (Pulsars shows the famous lighthouse effect). The fastest rotating Neutron star is PSRJ1748-2446ad having rotation rate of 716 rotations per second.

 Simulated view of a Neutron star. Due to its strong gravity, the background is gravitationally lensed, making it appear distorted.                                                                                                                                                                                         In just the first few seconds after the star begins it's transformation into a Neutron star, the energy leaving in neutrinos is equal to the total amount of light emitted by all the stars in Observable Universe . According to research , we know that the gravity and magnetic field is so strong that it can flatten everything on its surface, so if life is able to exist on Neutron star it must be two dimensional. Due to the strong gravity of Neutron star it shows the effect of gravitational lensing. Approximately, there are 100 million Neutron stars present in our milky way galaxy but the closest Neutron star to Earth is 500 light years away. On December 27,2004 , we find a gaint gamma ray flare from Magnetar SGR1806-20 which is 50000 light years away, in 0.2s it gives as much energy as given by our Sun in 300000 years.