• neutron star merger is the stellar collision of neutron stars. When two neutron stars fall into mutual orbit, they gradually spiral inward.
  • Neutron stars are the result of a massive star’s core collapsing under its own gravity during a supernova explosion. The extreme pressure crushes protons and electrons together to form neutrons, leaving behind a very dense stellar remnant.
  • Do not underestimate the sheer mass of neutron stars. These cosmic giants pack a punch, with a mass that surpasses that of the sun, all crammed into a sphere a mere 10-15 km in diameter.
  • Think of it like cramming Mount Everest into a marble. However, they still have some physical size, which means their density is finite.
  • On the flip side, black holes are a whole different ball game. They defy our understanding of physics, existing as points of infinite density, aptly named singularities. 
  • And then there’s the event horizon, the enigmatic boundary of a black hole. It’s the only aspect we can measure, adding to the intrigue of these cosmic phenomena. Neutron stars are not just dense; they are mind-bogglingly massive. Imagine a mass more significant than that of the sun, crammed into a ball only 10-15 km across. Neutron stars radiate very little electromagnetic radiation.
  • It’s like trying to fit the colossal Mount Everest into a tiny marble. They still have some physical size, which means their density is finite. On the other hand, black holes are a whole different ball game. They are not just points of infinite density; they are singularities surrounded by a region of space where nothing can escape, not even light. The region is called the event horizon, and it is the only thing we can measure about a black hole.
  • Black holes are way denser than neutron stars, and here is why. Don’t get me wrong; neutron stars are super thick. They have a mass more significant than that of the sun squeezed into a ball only 10-15 km across. Think of it like trying to fit a large amount of data into a small USB drive. The more data you try to fit, the denser the information becomes. However, they still have some physical size, which means their density is finite.
  • On the other hand, black holes are a whole different ball game. They have no physical size. They are just points of infinite density called singularities, shrouded in a region of space where nothing can escape, not even light. It’s a cosmic mystery that continues to fascinate and intrigue us.
  • A neutron star is a very dense, small stellar remnant left after a supernova explosion, while a pulsar is a type of neutron star that emits beams of radiation which appear to pulse as the star rapidly rotates, making it look like a cosmic lighthouse; essentially, a pulsar is a neutron star that we can observe as a result of its strong magnetic field and rapid spin, causing beams of radiation to sweep across our line of sightA neutron star is a very dense, small stellar remnant left after a supernova explosion, while a pulsar is a type of neutron star that emits beams of radiation which appear to pulse as the star rapidly rotates, making it look like a cosmic lighthouse; essentially, a pulsar is a neutron star that we can observe as a result of its strong magnetic field and rapid spin, causing beams of radiation to sweep across our line of sightA neutron star is a very dense, small stellar remnant left after a supernova explosion, while a pulsar is a type of neutron star that emits beams of radiation which appear to pulse as the star rapidly rotates, making it look like a cosmic lighthouse; essentially, a pulsar is a neutron star that we can observe as a result of its strong magnetic field and rapid spin, causing beams of radiation to sweep across our line of sightA neutron star is a very dense, small stellar remnant left after a supernova explosion, while a pulsar is a type of neutron star that emits beams of radiation which appear to pulse as the star rapidly rotates, making it look like a cosmic lighthouse; essentially, a pulsar is a neutron star that we can observe as a result of its strong magnetic field and rapid spin, causing beams of radiation to sweep across our line of sightA neutron star is a very dense, small stellar remnant left after a supernova explosion, while a pulsar is a type of neutron star that emits beams of radiation that appear to pulse as the star rapidly rotates, making it look like a cosmic lighthouse; essentially, a pulsar is a neutron star that we can observe as a result of its strong magnetic field and rapid spin, causing beams of radiation to sweep across our line of sight.
  • That region is called the event horizon, a boundary beyond which nothing, not even light, can escape the gravitational pull of the black hole. It’s the only thing we can measure about a black hole, and it’s crucial for understanding its properties.
  • Pulsars are one type of neutron star whose jets we observe using radio telescopes. They pulsate (get it?) rapidly as the neutron stars spin and their jets sweep across our line of sight.
  • While neutron stars’ dark cousins, black holes, might get all the attention, neutron stars are the densest material we can observe directly. The horizon hides black holes.  \/We can’t see what’s going on inside. However, neutron stars don’t have such shielding.
  • We use the event horizon to proxy for a black hole’s size and divide its mass by volume to get its density. The density of a black hole is always higher than that of a neutron star, no matter how massive or small they are.
  • Consider a neutron star with a mass of 2 solar masses and a radius of 10 km. Its density would be about 3.6 x 1017 kg/m3. Let us take a black hole with the same mass as two solar masses. Its event horizon would have a radius of about 6 km, and its density would be about 1.5×1019 kg/m3. That’s a staggering 40 times denser than the neutron star. The difference is truly mind-boggling.