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Did you know that the Crab Nebula has a pulsar in it?In 1094 AD, a supernova, clearly visible in daylight, was witnessed and recorded in China and India, and the result of it can now be seen in space as the luminous Crab Nebula, measuring 10 light years wide and being lit by the Crab Pulsar in the center. At 9.7 kilometres wide, it rotates 33 times per second and has an extremely strong magnetic field. This magnetic field constantly hurls particles out of the inner part of the nebula and into the larger cloudlike part. Please click on thumbnails for enlarged version and simple explanation.
Images Copyright (C) NASA Space Telescope Science Institute. Back to TopDid you know that new technology is hastening our discovery of new pulsars?In Australia, the 1000th pulsar was discovered by scientists using a modern addition to radio telescopes, called the "multibeam receiver system". This apparatus enables the radio telescope to scan the sky with 13 beams concurrently, as opposed to one. Pulsars are being discovered 10 times faster than previously achieved. Back to TopDid you know that pulsars are also called neutron stars?Pulsars are also known as neutron stars because they consist of highly compressed neutrons within their outer shell of iron and nickel. This is because as the core of the star collapses inwards during a supernova, the electrons and protons smash together at such forces that they fuse and become one, and the addition of a proton's charge (+1) and an electron's charge (-1) results in a particle with a (0) charge, which is a neutron.
Back to TopDid you know that the mass of a pulsar is almost 1 1/2 times the mass of our sun?Indeed, the mass of a pulsar is about 1.4 times the mass of our sun! This means that if a chunk the size of a lump of sugar were put on Earth, it would weigh 100 million tons! The gravity of a pulsar is about 300,000 times the gravity on Earth! Back to TopDid you know that pulsars have magnetic fields?Pulsars have tremendously strong magnetic fields, which are 1 trillion times the size of the Earth's magnetic field. This leads scientists to believe that the pulsing of pulsars may be accredited to electrons which are accelerated at the magnetic poles of the pulsar, and shot out into space at the speed of light. From our vantage point on Earth, these pulses look like bursts of radiation.
(Pulsars are constantly rotating, not stationary as depicted in the animation) Back to TopDid you know pulsars are unsurpassed as timekeepers?Pulsars are so consistent in their emission of regular radio waves that, when picked up by radio telescopes, can be used to tell time with accuracy surpassing the atomic clock or anything else known to man. Some pulsars are accurate to within 1 second for every 10 million years, while the accuracy of the atomic clock is within 1 second in 1 million years. Did you know that pulsars are commonly confused with quasars? Indeed, because of their similar name, people often think quasars and pulsars are the same thing, or they are highly related. This is a myth, because quasars are actually objects in space that emit extremely powerful radio waves. Quasars are so strong that they can emit 100 times the amount of energy as the Milky Way, our galaxy. ** What's the difference between a pulsar and a quasar? ** Before answering this question, it should be noted that pulsars and quasars are completely different entities. A pulsar is a rotating, collapsed star, while quasars are so far away that they can only be identified (and therefore described) by the energy they give off. Some theories about quasars state that they may be distant galaxies with large black holes in their centres, which would explain the large amounts of energy given off. So... the differences between quasars and pulsars? 1) Quasars are much, much larger than pulsars. 2) Quasars give off much more energy than pulsars -- in the form of radio waves (the lower-energy form that all pulsars are known to give off), x-rays, gamma rays, and other forms of ultraviolet radiation! *Many pulsars give off x-rays, and 6 known pulsars give off gamma rays; but not as many, and not as powerful, as quasars! 3) There are a lot more differences! But since this site is about pulsars, you should look around to find more info about quasars. Here are some good places to start: http://www.phys.vt.edu/~jhs/faq/quasars.html http://home.achilles.net/~jtalbot/glossary/quasar.html
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