Patti Beres, age 9, of Coaldale, Alberta, Canada, for her question:

ARE THERE OTHER SOLAR SYSTEMS?

Years ago, nobody knew the answer to this question. Scientists suspected that there must be other solar systems in the universe. But this was just guesswork because nobody could prove it. Now we know for sure that this is so. For our clever scientists have found one or two planets, orbiting faraway stars  somewhat as the planets of our solar system orbit the starry sun.

This discovery, plus some other known facts, led to more guesswork. If there are a few other solar systems, most likely there are many more. Some scientists suspect that most of the stars in our galaxy may have planets orbiting them. If this proves to be true, there must be millions and perhaps billions of other solar systems.    Who knows, some of these faraway solar systems may have planets very much like the earth.