The earth, sun and other planets of the solar system are a tiny part of our galaxy, which is called the “Milky Way.” This name is derived from the Greek word galaxias, which means “milky way.”

Our Milky Way galaxy is only an average-size one. Yet it is immense, containing about one hundred billion stars, as well as the planets of our solar system and other material such as gases and dust. Its diameter is so vast that if you could travel as fast as the speed of light, 186,282 miles a second, it would take you 100,000 years to cross it! How many miles is that? Well, since light travels about six trillion miles in a year, multiply that by 100,000 and you have the answer: our galaxy is about 600 quadrillion miles in diameter! That is the number six followed by seventeen zeros.

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THE “MILKY WAY” GALAXY

(Our Solar System)

Our solar system looks immense, yet it is dwarfed when placed in its position in our “Milky Way” galaxy. There are billions of galaxies