| | | | | | |
| | |||||
|
Quasar 3C273Recent discoveries have lead to new insight into how quasars might work. Learning more about 3c273 and other quasars helps to discover more about the history, large-scale structure, and future of our universe. Our own group of galaxies is about ten billion years old. In some cases, the photons we observe from the most distant quasars are comparable to the age of our galaxy!Galactic Nuclei Thanks to radio and X-ray observation, it is now apparent that the centers of galaxies like our own are home to as-of-yet unexplained energetic reactions. Some galaxies are called active galaxies, as they are further away and their nuclei emit far more radiation than galaxies like our own. Quasars are the most energetic and distant of all three objects. It is believed that the nucleus of a quasar is so bright that it hides the relatively dim surrounding galaxy. The activity in the nuclei of galaxies and active galaxies has similar characteristics to the activity taking place in quasars, and since it is easier to observe, it helps verify theories that explain how quasars work. Black Holes What is the engine behind the massive amounts of energy released by quasars? A clue is provided by the jet of 3C273, a radio, optical and X-ray spike that extends over a hundred thousand light years into space. This pattern points to a rotating, supermassive object. According to theory, matter from the surrounding galaxy orbits this object in what is called an accretion disk. Whenever matter from the disk is pulled by gravity into the center, the resulting electromagnetic forces could produce a beam of high-energy particles that would be observed as a jet at radio, optical and X-ray energies.
Any object with enough mass to produce these jets of energy would certainly collapse on itself due to its own gravity. Also, both quasars and active galaxies are seen to have massive, dark objects at their core. In fact, the only object known to theory that fits these criteria is a black hole, an object so massive that not even light can escape its gravitational pull! |
||||||||||
Revised:
|
||||||||
