Aurora Borealis
An aurora is a natural light display in the sky , particularly in the polar regions , caused by the collision of charged particles directed by the Earth’s magnetic field . An aurora is usually observed at night and typically occurs in the ionosphere . These phenomena are commonly visible between 60 and 72 degrees north and south latitudes .
Información del powerpoint
- Fecha: 22/02/2014
- Tamaño: 6.48 MB
- Categoría: Lugares y Paisajes
- Autor: agnerz
- Formato: Office Power Point 2000/3