Mendenhall Glacier I've always thought of travelling in order to go on vacations to a country that has nature, history, beautiful buildings, and a different dynamic than here, in Chile. That country could be U.S.A, specifically the state of Alaska. I think that everyone is thinking: why Alaska? It's too cold to think to go there! Well, I think that's so beautiful because this state show us the most beautiful things that nature and chemistry elements could give us: northern lights. The northern lights are product of the sun radiation, composition and characteristics of our atmosphere. The auroras are collisions between electrically charged particles from the sun that enter the earth's athmosphere. The lights are seen above the magnetic poles of the northern and southern hemispheres. The lights appear in many colors, it depends on the type of gas particles that are colliding and the distance in which it happens, for example, molecules of oxigen at 96 km are yellow...