Do quasars travel at the speed of light? Why are there no nearby, or in other words, young quasars? How is the luminosity of a quasar generated? Are quasars dangerous? Are there any Hubble Telescope pictures of quasars or have they only been detected by radio telescopes? What is the distance to the farthest known quasar from earth?
What are other names for quasars? Quasars are very mysterious objects. Astronomers today are still not sure exactly what these objects are.
What we do know about them is that they emit enormous amounts of energy. They can burn with the energy of a trillion suns. Some quasars are believed to be producing 10 to times more energy than our entire galaxy. All of this energy seems to be produced in an area not much bigger than our solar system. A pulsar is a rapidly spinning neutron star.
A neutron star is the highly compacted core of a dead star, left behind in a supernova explosion. This neutron star has a powerful magnetic field. In fact, this magnetic field is about one trillion times as powerful as the magnetic field of the Earth.
The magnetic field causes the neutron star to emit strong radio waves and radioactive particles from its north and south poles. These particles can include a variety of radiation, including visible light. Pulsars that emit powerful gamma rays are known as gamma ray pulsars. If the neutron star happens to be aligned so that the poles face the Earth, we see the radio waves every time one of the poles rotates into our line of sight.
It is a similar effect as that of a lighthouse. As the lighthouse rotates, its light appears to a stationary observer to blink on and off.
In short: A quasar looks like a star when you see it in the sky, but if you look closer, there are a number of differences. First of all, quasars are the brightest objects in the universe and they shine anywhere from 10 to , times brighter than the Milky Way. Secondly, a quasar rotates very fast and emits enormous amounts of energy, this can be millions, billions, or even trillions of electron volts.
This is more than the sum of all the energy emitted by the entire galaxy the quasar is in. Finally, they only appear in galaxy's with super-massive black holes these particular black holes can contain up to billions of times the mass of the sun.
It took years of study to realize that these distant specks, which seemed to indicate stars, are created by particles accelerated at velocities approaching the speed of light. Scientists now suspect that the tiny, point-like glimmers are actually signals from galactic nuclei outshining their host galaxies.
Quasars live only in galaxies with supermassive black holes — black holes that contain billions of times the mass of the sun. Although light cannot escape from the black hole itself, some signals can break free around its edges. While some dust and gas fall into the black hole , other particles are accelerated away from it at near the speed of light.
The particles stream away from the black hole in jets above and below it, transported by one of the most powerful particle accelerators in the universe. Most quasars have been found billions of light-years away.
Because it takes light time to travel, studying objects in space functions much like a time machine; we see the object as it was when light left it, billions of years ago. Thus, the farther away scientists look, the farther back in time they can see. Most of the more than 2, known quasars existed in the early life of the galaxy.
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