Known unknown facts about Neutron star

by | Facts |

Known unknown facts about Neutron star

A neutron star is the collapsed core of a giant star which before collapse had a total of between 10 and 29 solar masses. Neutron stars are the smallest and densest stars, not counting hypothetical quark stars and strange stars. Born from the explosive death of another larger stars, Neutron stars tiny objects pack quite a punch. These are created when giant stars die in supernovae and their cores collapse, with the protons and electrons essentially melting into each other to form neutrons.

Neutron stars pack their mass inside a 20-kilometer (12.4 miles) diameter. They are so dense that a single teaspoon would weigh a billion tons — assuming you somehow managed to snag a sample without being captured by the body's strong gravitational pull. On average, gravity on a neutron star is 2 billion times stronger than gravity on Earth.

Mark Alford, a professor at Washington University, said, “Imagine a little lead pellet with cotton candy around it. That’s an atom. All the of mass is in the little lead pellet in the middle, and there’s this big puffy cloud of electrons around it like cotton candy.”

Here are some other the lesser-known facts about Neutron stars.

Let's explore them -

  • Neutron stars can spin as fast as 43,000 times per minute, gradually slowing over time.

  • In just the first few seconds after a star begins its transformation into a neutron star, the energy leaving in neutrinos is equal to the total amount of light emitted by all of the stars in the observable universe.

  • The fastest rotating neutron star ever recorded till date is PSR J1748-2446ad and it’s located in the constellation Sagittarius about 18,000 light years away from the Earth.

  • Most of the protons in a neutron star convert into neutrons—neutron stars are made up of about 95 percent neutrons. When protons convert to neutrons, they release ubiquitous particles called neutrinos.

  • Neutron stars are made in supernova explosions which are giant neutrino factories. A supernova radiates 10 times more neutrinos than there are particles, protons, neutrons and electrons in the sun.

  • Neutron stars have some of the strongest gravitational and magnetic fields in the universe.  The gravity is strong enough to flatten almost anything on the surface. The magnetic fields of neutron stars can be a billion times to a million billion times the magnetic field on the surface of Earth.

  • Neutron stars that can be observed are typically very hot, with surface temperatures that can be as high as 60,000K, compared to say around 6,000K for the Sun.

  • The figure of 100 million is based on standard models of galactic evolution and is further derived from the estimated number of supernova event that has occurred in the history of the Milky Way galaxy.

  • Only relatively young neutron stars are easy to detect, though, as most are cold, or slow rotators, or are not accreting material from companion stars, thus making them virtually undetectable.

Neutron star

  • Scientists first observed neutron stars in 1967, when a graduate student named Jocelyn Bell noticed repeated radio pulses arriving from a pulsar outside our solar system.

  • The 1993 Nobel Prize in Physics went to scientists who measured the rate at which a pair of neutron stars orbiting each other were spiraling together due to the emission of gravitational radiation, a phenomenon predicted by Albert Einstein's general theory of relativity.

  • In all known cases, the periodic magnetospheric pulses coincide with the stars’ rotational period, thus, a neutron star becomes a pulsar, pulsating radiation that can be detected as originating from the star.

  • A neutron stars’ gravitational field can be so strong that light emitted from it cannot escape since it is caught in an orbit around the star. In such a case, the entire surface of the star is visible from just a single point of observation.

  • In cases where a neutron star accretes matter from a normal companion, the matter is sucked up like a sponge, which can increase a neutron star’s rate of rotation by as much as 100 revolutions per second in the case of millisecond pulsars.

  • At least two neutron stars are known to have planets, although the origin of these planets is not certain. It is thought that in some cases, the planets may be original, in the sense that they survived the formation of the neutron star, or that they may have been captured.

  • A neutron star is perfectly capable of completely stripping the outer layers off of a main-sequence companion star, which would leave a planetary-mass object.

  • Back in 2007, a group of researchers discovered a peculiar X-ray source in the constellation of Ursa Minor about 250-1000 light years away, which they later identified as a neutron star. It is quite possible that it could be the closest neutron star to Earth. Officially designated as 1RXS J141256.0+792204, the neutron star is nicknamed Calvera after the antagonist of the popular 1960s movie “The Magnificent Seven”.

Neutron star

  • According to an estimation based on the number of supernova explosions, there should be about 100 million to one billion neutron star present in our Milky Way galaxy.

  • The temperature of the core to about 5×109 Kelvin. At this temperature, high energy gamma rays are produced, which breaks down the iron nuclei into what is known as alpha particles.

  • Since the Neutron Stars rotate at extremely high speed and they have extreme gravity, the spin produces strong magnetic fields. Because of this, Neutron Stars emit radiation from their spin axes.