What is a Quasar?

Do you ever wondered, whether all those things that twinkles in the sky are stars?
well, twinkling is not just for stars. There are some far more interesting space objects that live under the mask of a star, and you can never distinguish them from stars unless your telescope is made to detect infrared radiation.

Quasars, this is what they--good scientists :-)--named them as they are quasi-stellar radio sources.

Quasar actually is a compact object like star rather than a expanded one like galaxy, surrounding a super massive black hole that lie at the center of a super massive galaxy. This super massive black hole in fact is responsible for all the power it is exhibiting.

They are by far the most luminous, most powerful and most energetic objects in the universe.
The energy they emit is in the range of about 1000 times that of the galaxies they inhabit in. They even show the heavy red shift (if a light source accelerates away from us, it appears more and more red) from earth, and that means they are moving faster away from earth and when combined with Hubble's law (galaxies tend to move away from each other with a velocity proportional to their distance) it shows that they are very very far from earth, and if this is the case, it can also implies that they are formed much early in the universe(as they traveled a lot of distance so far)

There are some very high radiating quasars in our known universe and their radiation almost equals trillion sun's--may be that's why they stay far away or is it the other way around. :-)

There is even a possibility that our Milky Way was once a quasar(according to NASA), may be because they didn't found any quasar at its center surrounding the massive black hole ;). The question is if it was once a quasar, what happened to the galaxy it was once surrounded by?