3 - Astornomy

03 Neutron Stars

Scientists theorized as early as the 1930s that something like a neutron star could exist, though it was a while before they saw their theory materialize.

The accidental discovery of a neutron star in 1967 by graduate student prove this theory to be true.

The student was scanning the sky, hoping to observe radio signals, when she saw an unknown object that blinked at regular intervals.

The source, scientist later discovered, was a neutron star.

A neutron star is formed when a massive star explodes into a supernova.

As the massive star explodes, the majority of the outer mass of the star is sent into space.

Only a small remnant of the star remains intact at its core.

As the core collapses from the explosion, the protons (the part of an atom with a positive charge) and electrons (the part of the atom with a negative charge) within the remnant combined to form neutrons (the part of an atom with no charge), thus giving neutron stars their name.

Neutron stars are not actually stars in the sense that their nuclear reactions have ended forever.

Scientists likely gave it the name of “star” because it is a stellar object that can sometimes be seen from Earth.

Neutron stars have several unique characteristics. First, they are some of the densest objects in space.

One teaspoonful of material from a neutron star would weigh over ninety thousand kilograms.

A neutron star has a mass of at least one-and-a-half times the mass of the sun.

All of the mass is compacted into an area that is no more than ten to twenty kilometers in diameter.

This is the same size as a large city on Earth or a small asteroid in space.

Secondly, neutron stars have extremely strong magnetic fields. During the supernova when a neutron star is formed, the massive parent star’s magnetic field is compressed.

This means that the magnetic lines are squeeze close together, and this results in a neutron star with a magnetic field that is trillions of times stronger than the Earth’s.

Thirdly, the gravitational force on a neutron star is much stronger than the gravity on Earth.

A seventy-kilogram person would weigh the equivalent of one billion kilograms on a neutron star.

The gravitational pull on the neutron star would flatten a person thinner than a piece of paper.

Neutron stars are distinctive and yet another way. They rotate very rapidly with rotations measuring just fractions of a second.

By comparison, the massive star that exploded to form the neutron star might have only rotated once every two weeks.

The neutron star spins so much faster because of its tiny diameter. Envision an ice skater spinning; as she draws her body and closer, making it smaller, she picks up speed in her rotations.

The neutron star is the same as the remnant of the parent star takes a new, smaller form, it begins to rotate faster.

As the neutron star spins, it emits energy. In reality, it sends a constant stream of light into the atmosphere, but the multiple rotations each second produce what seems to be pulsing light from the neutron stars.

Neutron stars that send out these seeming pulses of light are called pulsars.

It was the blinking light sent out by these rotating neutron stars that led researchers to their discovery.

There were several subtypes of stars within the category of neutron stars, all with their own distinctive characteristics.

Most neutron stars emit energy or radiation and are classified as radio-emitting neutron stars.

Pulsars are one such subtype. Binary pulsars are another type. These are pulsars that have a star alongside them in their orbit.

A small number of neutron stars are considered to be radio-quiet, which means they seem to emit no radiation, though scientists hypothesize that these neutron stars simply do not pulse in our direction.

Magnetars are a type of neutron star that have a magnetic field even stronger than that of any other neutron star.

The study of neutron stars is relatively new to scientists in the field of astronomy. Having been discovered less than fifty years ago, scientists still have much to learn about neutron stars.

The information they have been able to gather has shown that neutron stars promise to provide complex behavior for researchers to study for years to come.