One - third of the world 's population - including 80 % of Americans - can no longer see the Milky Way .
Grand Canyon National Park is one of the last places in the United States where one can experience a star - filled night sky .
One - third of the world 's population - including 80 % of United States - can no longer see the Milky Way .
Grand Canyon National Park is one of the last places in the United States where one can experience a star - filled night sky .