Ruth Hosking, age 13, of Rapid City, S.D., for her question:

WHAT IS A QUASAR?

A quasar is a galaxy that gives off a great deal of energy from &70 its central area. This energy is radiated by the quasar in the form   of light and radio waves.

Some quasars, scientists tell us, are located near the edge ofthe universe. It takes light, which travels 186,282 miles per second, about 10 billion years to travel from such quasars to the earth.

A quasar can release about 100,000 billion times as much energy as the sun dogs. We don't know how a quasar generates so much power, but some scientists believe the energy results from collisions between fast moving stars in the central part of a quasar.

Quasars were first observed in 1960 by a group of astronomers at the Palo mar Observatory in California. By the mid 1970s, about 500 quasars had been discovered.