Stay up to date with notifications from The Independent

Notifications can be managed in browser preferences.

Picture of the Day: Green sky at night, northern delight...

Tuesday 15 February 2011 01:00 GMT
Comments

The aurora borealis, or northern lights, hangs like a fluorescent curtain over the village of Ersfjordbotn, near Tromso in northern Norway.

The atmospheric phenomenon is caused by streams of electrically charged particles from the Sun, which are funnelled to the polar regions by the Earth's magnetic field. As the particles hit atoms in the upper atmosphere they excite them to higher energy levels, and this energy is then released in the form of light. This aurora is caused by the excitation of oxygen atoms, which emit a characteristic green coloration.

Join our commenting forum

Join thought-provoking conversations, follow other Independent readers and see their replies

Comments

Thank you for registering

Please refresh the page or navigate to another page on the site to be automatically logged inPlease refresh your browser to be logged in