Science Videos These are some of my favorite Science video s from Youtube.  I believe that all of these  videos are non-copyrighted and in the public domain. I hope you enjoy them. Most students think that the Earth is HUGE.  Well,  it is...compared to ourselves.   But, compared to some of the other planets, its pretty small.  Compared to the sun, it’s postively tiny.  And, compared to some of the other stars its... Well, watch the video and see for yourself. Our sun is a star, and there are billions and billions of stars in the Universe.  How big is our solar system?  How big is our galaxy (the Milky Way)?  How big is the Universe? On Earth, when we think about distance, we use feet, inches, miles, or maybe kilometers.  The Universe is so huge, however, that those units are not very useful to describe distances in space.  Scientist use “Light Years” when talking about the size of the Universe.  A light year is the distance light itself travels in one year.  It takes light from the sun about 8 minutes to get to Earth.  If we sent the fastest rocket known to man the same distance, it would take about a YEAR to get there.  There are billions of stars in the Universe.  If we could travel at the SPEED OF LIGHT (we can’t) , it would take 4 YEARS to get to the nearest star (other than the Sun).