Heavenly Bodies
Quasars are the brightest celestial objects in the universe and for a long time were considered as being among the stars. Quasars are much smaller than galaxies, but they are brighter than hundreds of galaxies. These objects were discovered in 1960, but astronomers only reached an agreement about their nature in 1980. They came to the conclusion that a quasar is a compact region at the center of a large galaxy that has a black hole within it. The energy released from a quasar can be as much as 1000 times the energy released from the entire Milky Way. To date, more than 200 thousand quasars have been identified and the nearest of them to us is 600 million light years away, while the furthest one is 28 billion light years away. If you ponder upon these numbers and dimensions, you will realize that the earth, with all its grandeur and vastness, is equivalent to a drop in the ocean. Now, think about how much space you occupy in this world.