Neutron Stars

1. 1 solar mass black hole (smallest)
2. 1 solar mass white dwarf
3. 1 solar mass star
4. 1.5 solar mass neutron star (largest)

A black hole has an event horizon, beyond which nothing can escape, including light. Neutron stars also have an event horizon, called the "surface" or "crust," which marks the boundary within which matter is crushed by extreme gravity. White dwarfs, being less massive, do not have an event horizon.

A neutron star is so dense that one teaspoon (5 millilitres) of its material would have a mass over 5×1012 kg or 5,500,000,000 tons. About 900 pyramids of Giza.

The resulting force of gravity is so strong that if an object were to fall from just one meter high it would hit the surface of the neutron star at around 2,000 kilometres per second, or 4.3 million miles per hour.

See related question.

The Sun will never leave behind a stellar remnant such as a neutron star, as it does not have enough mass to achieve the massive pressures required to make one.

Our Sun will end up as a white dwarf stellar remnant.

No. Due to the massive gravitational pull - all atoms have been reduced to major and minor subatomic particles clumped together. Therefore, there are no discernible individual atoms and hence no elements.

Stars that are too massive to form neutron stars can undergo a supernova explosion and collapse into a black hole. This process occurs when the core of the star collapses under its own gravity, creating a region with infinite density and strong gravitational pull from which not even light can escape.

Neutron stars do not produce visible light on their own. However, if a neutron star is part of a binary system and is accreting material from a companion star, the accretion process can generate intense X-ray emission which can appear blue. This is known as an X-ray binary system.

Adding more mass to a 1.4-solar-mass neutron star could potentially push it beyond the limits of neutron degeneracy pressure, causing it to collapse further. This could result in the formation of a black hole if the mass exceeds the Tolman-Oppenheimer-Volkoff (TOV) limit for neutron stars.

No, low mass stars do not become neutron stars. Low mass stars like the Sun end their lives as white dwarfs. Medium mass stars can evolve into neutron stars, but they must first go through the supernova stage to shed their outer layers and leave behind a dense core of neutrons.

A small star that only gives off faint light and is relatively cool is likely a red dwarf star. These stars are much smaller and cooler than our Sun, but they are the most common type of star in the universe. Despite their dim appearance, red dwarfs can be very long-lived.

Yes, both black holes and neutron stars are remnants of the death of massive stars. Neutron stars form when the core of a massive star collapses but does not produce a black hole. Black holes are formed when the core of a massive star collapses beyond the neutron star stage.

Astronomers can infer the presence of an unseen star in a system through its gravitational influence on the observed star(s). This influence can manifest as deviations in the star's orbit or variations in its brightness or spectral features. Techniques such as astrometry, radial velocity measurements, and gravitational lensing can also be used to detect the presence of unseen stars.

When we observe the sun, we are actually seeing the sun as it was about 8 minutes ago because it takes light approximately 8 minutes to travel from the sun to Earth. So, in a way, we are always looking at the sun with a slight time delay.

This is because of a law called conservation of angular momentum. If a star - which will usually have some rotation, and therefore some rotational momentum - collapses to a size of 20-30 km., angular momentum is conserved. Since the diameter decreases, it must spin faster. (Angular momentum is the product of a quantity called moment of inertia, which depends on the diameter of an object, and angular velocity.)

The story begins when 1) an aging star swells to a red giant, and 2) it explodes in a Type II, Type Ib, or Type Ic supernova, then 3) it leaves behind a cooling core that forms the ultradense neutron star.

A link is provided to the Wikipedia article on the neutron star.

The mass of a star which is 1.4 to just under 3 times the mass of the sun provides a scenario where that star has used up its hydrogen fuel and the core begins to change the overabundance of helium into carbon then eventually into silicone and so on until the transference no longer produces energy which happens when the core goes to iron. Then the two forces that are constantly in conflict in the nature of stars becomes out of balance. Gravity is the winner and the thermonuclear forces begin to shut down. This is not a gradual process at the end. This is the same process that occurs in the death of any star. However, a star this big suddenly the whole core collapses in an actual instant. The outer layers of the star are blown off in a cataclysmic explosion. The gravity crushes the atoms which compose the core that did not blow off in the instantaneous explosion of its outer layers. This crushing gravity is not enough to cause a "Black Hole," but it is enough to make the electrons in the shell of those atoms combine with the protons in the nucleus of those atoms turning them into neutrons. The entire star with a diameter of well over a million to 3million miles reduces down to the diameter about the size of a city, maybe twenty miles across. The surface has the smoothness of a cue ball. On an object the diameter of a city there is hardly a bump even a millimeter high. These things spin at fantastic rates in some cases thousands of times a minute. This causes an electromagnetic emission which is focused at the poles of this spin and is intense in its strength. These signals can often be detected many light years away. This material that composes the neutron star, the size of a teaspoon might weigh 5,000 tons. All this leads to one of the most bizarre objects in our Universe.

Yes, a neutron star is much more massive and denser than a planet. Neutron stars are formed from the remnants of massive stars and are typically only a few kilometers in diameter, while planets can be thousands of kilometers in size.

1,100,000,000,000 kilograms = 1.21254244 × 109 short tons

Neutron stars emit light energy primarily through the release of stored thermal energy. They are incredibly hot due to their dense composition and high temperatures, leading to the emission of X-rays, gamma rays, and sometimes visible light. This thermal radiation results from the intense pressure and nuclear reactions still occurring within the star's core.

It is not actually on any of their cds because it was made specifically for the Twilight: Eclipse Soundtrack.

When fusion stops in a star it will start to fuse helium and will become a red giant.

In a supernova explosion, the core of the star typically, we believe (because we've never had an actual example to study) collapse into a black hole. There may be some cases in which the core is "only" compressed to neutron-star density, but our understanding of the mathematics of extreme gravity and pressure is a little weak around the edges there.

A cubic centimeter of neutron star material would weigh approximately 400 million tons, which is equivalent to 4,000 aircraft carriers. Neutron stars are incredibly dense, with material packed tightly together due to the immense gravitational forces at play.

Hardly any - they are very far away. However, a supernova (which would come before a neutron star) could have catastrophic effects on Earth, if it were to happen in our neighborhood (up to a few thousand light years!).

It means it's mass is very high and its volume is very low. A standard neutron star has a mass thousands of times greater than the sun, but a volume of a small city. This ridiculously high density and pressure also account for the high temperatures of neutron stars. PS. Quark stars are denser than neutron.