Southern Lights show a 'truly spectacular experience'

The aurora australis has made a spectacular return to New Zealand skies, with people reporting displays of the Southern Lights from all parts of the country on Friday night.

This year, the Southern Lights have been unusually active, as the sun undergoes a period of intense activity, which occurs in 11-year cycles.

People have shared photos with the Otago Daily Times of images captures in parts of the South, while RNZ is reporting impressive photos being sent from around Canterbury and all the way up as far as Northland in the North Island.

Madison Murray, who took photos from the Crown Range near Queenstown, said it was the "most impressive show of an aurora I've ever seen".

"Even with the naked eye you could see the whole sky dancing. A truly spectacular experience."

Aurora displays are related to activity from the sun.

Usually particles from solar flares bounce off the Earth's magnetic field, but when there is a severe eruption, they can penetrate the ionosphere and interact with gases around the magnetic poles - causing the ribbons of colour.

Auroras are usually confined to certain latitudes in the north and south, which makes them relatively rare to observe for most of the population.

The pinks, purples and greens that are often associated with aurora are the particles interacting with different gasses. Simply put, oxygen - which emits greenish-yellow or red light - and nitrogen - which emits blue light - in the upper atmosphere release specific colours when bombarded by solar radiation.

Atoms, molecules and ions in the atmosphere are excited by the electrically charged particles and, in turn, release photons - which is the light we see.

 - RNZ/ODT