But how can this be done? You can make something really dense by squishing the molecules together, or you can look at individual atoms and squish the electrons and nucleus together. Both are ways of increasing the density of a certain object, but the most efficient way is to decrease the distance between the nucleus of an atom and the surrounding particles; thus, you would look at individual atoms. On earth, the average distance the two are huge. If you were to place a golf ball representing the nucleus, then the electrons would be several miles away. But when a pulsar forms, the most of the particles and mass are not expelled into outer space; instead, all that compresses inward so that the protons and electrons are now brought fairly close to the nucleus. So, instead of being several miles away, our electron representatives are only circling 4 to 5 feet away from the golf ball nucleus. In fact, the average pulsar is more than 100 trillion times denser than water!

A star has to psas a certain limit to end up as a pulsar. This is called the Chandrasekhar limit, named after a famous scientist who discovered it and put it at 1.4 solar masses. So, if a star has a mass less than 1.4 of that of our sun, it will become a white dwarf; wihle those, which have masses larger than 1.4 will become pulsars, neutron stars, or blackholes. Most pulsars have a lifetime of 3 - 4 million years or so. Others can live up to 20 million or less than 0.5 million.

Because pulsars are so small, they can only be detected with radio telescopes. On the other hand, it is relatively easy to detect pulsars using radio telescopes than to find stars using optical telescopes. That is because they are extremely powerful radio beacons, sending out signals that our telescopes can easily detect.

But radio telescopic signals can’t tell astronomers a lot about pulsars; the pulses only tell them how fsat it is spinning and whether or not it has other objects orbiting it. Also, they can probabyl figure out how far away the pulsar is from earth, how many planets or bodies are circling it, and that’s the extent of what can be gained. Statements about what the surface looks like, the interior and chemical composition mainly rely on hypotheses and theories.

As far as we know, the surfaces of pulsars are solid and extremely smooth, so that you would need a 400x microscope to detect the slightest fault. There are also tiny bumps, which are no more than an inch high at the most. But because of the pulsar’s enormous gravity, it would take a human all the energy generated in his or her lifetime to climb to the summit of the bumps. In some places, there are tiny crevices on the surface that are no more than a millionth of an inch, produced by “starquakes”. But again, because of the gigantic gravitational pull, the experience of a “starquake” is equal to that if a part of the earth’s crust crashed down 100 miles. These mini but deadly quakes are actually the cracking of the surface, which are caused by the flattening out of a central bulge. Pulsars are wider at the center because of its fast rotation rate. Over time, after releasing a lot of energy, the spin rate slows down considerably. This slowing-down process causes the center area to bulge out, thus creating the tiny starquakes. During these miniature quakes, the rate of rotation rises briefly, lasting for only 100 billionth of a second on the average.

       

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