Through much of human history, our ancestors looked up at a night sky filled with stars that set planting patterns and helped lead them across continents. We've since filled that night sky with artificial light, brightening our immediate surroundings and dimming the stars above. New York City residents can live their entire lives seeing fewer than a dozen of the brightest stars and planets. Most people living east of the Mississippi River will never see the Milky Way in all its sparkling glory.