Disclaimer: The following was written several years ago as a sixth grade research project. Please do not squander your precious time e-mailing me and pointing out all the various errors and inconsistencies, because the value of this work is of a “historic” nature only. Allow this project to entertain you with its ignorance, and enjoy! ;-)

Pulsars: A Unique Addition to Our Understanding of the Universe

Nine hundred years ago in a galaxy far, far away, a giant star thousands of times more massive than our sun exploded, and created a cloud of gas. Now, all that was left was a relatively small chunk of material – the core. In a moment, the dead star’s core began to contract and in the act, grew denser, pulling all the atoms and their components together. At the same time, it started to spin at more than 1000 times per second! All happened so fast that, before long, the star had begun its second life as a pulsar.

The event was recorded in the pages of medieval philosophers in A.D. 1054, but it was not until 1967 that Antony Hewish and his student, Susan Jocelyn Bell, detected the residue of that catastrophe. Hewish was a professor at Cambridge University in England at the time, and he had set up a complicated radio telescopic system covering some 18 square kilometers. Along with his student, the two began searching for other objects in the universe. In 1967, they found what they were looking for. The only problem was that they did not know what it actually was. Thus, they decided to search for others of the same breed. A string of findings followed, and after a year or two, Hewish and Bell felt confident enough to announce their discovery. But even after the discovery of dozens of other such objects, the major question was still not solved: what exactly is this thing?

At the present, we have solved that problem, thanks to research and better telescopes. This mysterious object is called a pulsar. The word pulsar can somehow be translated to “pulsating star” for that is what a pulsar really is. The most defining characteristic of a pulsar is its extremely rapid and regular spin, which, in some pulsars, can be 1000 times per second. The next one is its gyrating and exceedingly intense magnetic field. The third is that it is only 10 miles across for most. Also, pulsars are super dense, for they are just as massive as our sun but all those atoms have contracted into a ball that’s only several miles in diameter!

Surprisingly, some celestial objects have these properties. For example, a white dwarf, a faint remnant of a star, has a strong, spiraling magnetic field, which can sometimes be as powerful as a pulsar’s. But very few white dwarfs have been detected with half as strong a field. So for the present, scientists can only assume that such powerful ones are very uncommon among white dwarfs. There is another star that has a pulsar trait: the neutron star. A neutron star is small, super dense and has a gyrating magnetic field, but it lacks the extremely regular spin that all objects have to have if they can be qualified as pulsars. Thus, it is wise to give the second definition of a “pulsating neutron star”.

But how could any object spin up to 1000 times per second? First of all, a pulsar is very, very small and as most people would argue, small things can spin faster than large things, so a small size would help the pulsar to spin very fast. Second of all, a pulsar has an unmatched gravitational force that helps to pull things together. Once an object is rotating rapidly, it tends to throw things out; very much like if one were to drive a car round and round in circles with a light box on the other seat with the door open. The box would eventually fall out, but that would never happen if there was a strong gravitational force to hold it in place. A pulsar is similar to the “rotating car model”. If its gravitational field were not as strong, then particles would shoot off from the surface and soon, the whole pulsar would collapse. But fortunately, pulsars have both small size and an intense gravitational field, which enables them to be what they are.

       

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