Laura Tobin Instagram – What colour #Aurora did you see? (For some reason it’s made it dimmer, it was brighter by eye) Auroras can appear green, pink, dark red, blue, purple and even yellow! Auroras are caused by energized particles from the sun slamming into Earth’s upper atmosphere at speeds of up to 45 million mph. Earth’s magnetic field then redirects the particles toward the north and south poles.  The electrically charged particles then enter Earth’s atmosphere, exciting gas atoms and molecules and generating auroras. The most common aurora color is green.  Green auroras are typically produced when charged particles collide with high concentrations of oxygen molecules in Earth’s atmosphere at altitudes of around 60 to 190 miles (100 to 300 kilometers), Red auroras are comparatively less frequent and are usually associated with intense solar activity.  They occur when solar particles react with oxygen at higher altitudes, generally around 180 to 250 miles (300 to 400 km)